(Management shakeups article updated with latest shakeup in GM, Dynegy and American Eagle Outfitters)

NEW YORK ( TheStreet) -- Barely three months into 2011, and the Street has already seen several prominent management shake-ups that could change the course of some of the biggest companies, including Google ( GOOG - Get Report), AMD ( AMD - Get Report) and Citigroup ( C - Get Report) and General Motors ( GM - Get Report).

Could this be a sign of things to come?

"We could see more changes like this as the economy continues to pull out of recession," noted John A. Challenger, chief executive officer of the global outplacement firm Challenger, Gray & Christmas in the January report on CEO departures. "Despite evidence that stability at the top is a key element to long-term success, many companies feel that certain CEOs are better suited for holding the ship steady through rough waters, while others are better for expansion," he said.

According to Challenger's data, 2009 and 2010 saw fewer CEO exits, possibly reflecting an unwillingness to rock the boat at the height of the recession.

Through the first two months of the year, a total of 188 CEO departures have been announced, which is down 15 percent from 2010 when 221 chief executives left their posts in January and February.

Tech companies led the shakeups in January, while the financial, non-profit and healthcare sectors saw the biggest turnover in February. The top reason for CEO departures so far this year has been resignations.

Shareholders often worry about the impact on the company as it transitions under a new management. They tend to favor companies that have a clear succession plan in place and see sudden changes as a sign of trouble.

In the cases of struggling companies however, a change in management is usually seen as a welcome opportunity to overhaul strategy.

Read on to find out which of your companies are seeing big changes in their executive ranks.

General Motors

Chris Liddell, CFO of GM, Steps Down

General Motors ( GM - Get Report) announced March 10 that its CFO Chris Liddell will be leaving the company on April 1 after helping the company complete its record IPO and overseeing its return to profitability.

Dan Ammann will succeed Liddell as General Motors chief financial officer, effective April 1. Ammann, 38, is currently GM vice president, finance and treasurer.

Liddell, 52, joined GM in 2010 and led the company's financial and accounting operations on a global basis.

"I came to General Motors to be part of something great," said Liddell. "My objective was to help rebuild this iconic company and I am particularly pleased that through this process, we have also developed a strong successor in Dan Ammann."

CEO Dan Akerson said Amman has been actively engaged in the financial strategy of GM and helped reduce its debt. Prior to joining GM in 2010, Amman was head of industrials investment banking at Morgan Stanley ( MS).

Dynegy

Bruce A. Williamson, president and CEO of Dynegy, stepped down in February

Dynegy ( DYN) announced on March 9 that it had elected four new directors to the board, including two elected by activist investor Carl Icahn.

The four new directors -- Thomas Elward, Hunter Harrison, Vincent Intrieri and Samuel Merksamer -- have been named as the sole members of the board's governance and nominating committee, charged with the responsibility of searching for a permanent CEO and additional qualified director nominees to stand for election at the company's annual shareholder meeting. They will also serve on the board's special committee for finance and restructuring.

Harrison was nominated by Seneca Capital. Intrieri and Merksamer were nominated by Icahn Associates.

The appointments follow the recent resignation of two senior executives at Dynegy after shareholders rejected Icahn's $665-billion takeover bid, the second takeover offer the power generation company had received.

On Feb. 21 it was announced that President and CEO Bruce A. Williamson was stepping down and that five of the company's remaining directors on the board will not be standing for re-election. CFO Holli Nichols also left the company for a different opportunity.

Dynegy said the decision to replace the board was a recognition of "the desire of stockholders to pursue a different path."

Dynegy had been a target for several months, with the management contending that a buyout would be in the best interests of the company in an unfavorable market for power generation companies.

Shareholders, led by Seneca Capital, deemed Icahn's bid of $5.50 a share too low. Earlier, they rejected a bid from Blackstone ( BX) for $5 per share.

Dynegy now says it might have to explore seeking bankruptcy protection if it fails to renegotiate credit agreements with banks.

American Eagle Outfitters

James O'Donnell, CEO, resigns on March 9

After much speculation, American Eagle Outfitters ( AEO - Get Report) CEO announced his resignation on March 9.

James O'Donnell, 70, will continue at the teen retailer until a replacement is named.

O'Donnell joined American Eagle as chief operating officer in 2000, was then appointed Co-CEO in 2002 and was named CEO in 2003.

In recent years American Eagle has struggled to compete against rivals Abercrombie & Fitch ( ANF) and Aeropostale ( ARO). The company became even more strained when Abercrombie began lowering price points amid the recession.

"O'Donnell was on the hot seat coming into 2011 as a result of poor relative performance in 2010," analyst Brian Sozzi wrote in a note. "While other teen apparel chains returned to some form of health last year, reflecting the recharged U.S. consumer and more interesting products and promotions, American Eagle generally had inconsistent performance."

MF Global

COO Bradley Abelow assumes additional title of President

MF Global Holdings ( MF) announced several changes to the top on March 7.

The brokerage, which is run by former New Jersey Governor Jon S. Corzine, announced the appointment of Henri Steenkamp, the firm's current chief accounting officer and global controller, as chief financial officer. Steenkamp, will replace Randy MacDonald, who was named global head of the company's retail operations.

Also, Chief Operating Officer Bradley Abelow will assume the additional position of president of MF Global, effective immediately. Abelow will be responsible for further developing and executing the firm's new strategic direction, while continuing to oversee risk, operations, transaction services, human resources, information technology, procurement and real estate activities for all MF Global entities.

Abelow joined the company in 2010 and was previously a founding partner of NewWorld Capital Group, a private equity firm.

Steenkamp, 34, has been with the company since 2006 and was at PricewaterhouseCoopers for eight years before that.

St. Joe

Bruce Berkowitz, Fairholme Capital Management

Florida-based real estate developer St.Joe ( JOE - Get Report) announced the appointment of Bruce Berkowtiz, founder of Fairholme Capital Management ( FAIRX), as Chairman of its newly-formed board of directors on March 4, and appointed ex-chairman Hugh Durden to fill in temporarily as CEO.

The latest appointments are a result of a major management shakeup at St. Joe on the back of strong pressure from Fairholme Capital, its largest shareholder. Earlier last week, the company announced the resignation of CEO and President Britt Greene. Greene had been with St. Joe for 13 years. Three board members -- Michael Ainslie, John Lord and Walter Revell -- were replaced by four new directors proposed by Fairholme, including Berkowitz, Fairholme President Charles Fernandez, former Florida Gov. Charlie Crist and Carnival COO Howard Frank.

The latest developments are a victory for Berkowitz who had been butting heads with management over the company's business model. Berkowitz has long held the view that the company is undervalued, but has also said that its business model had operational inefficiencies that burned cash.

The battle for control for St. Joe began heating up in mid-February after Berkowitz and Fernandez resigned from the board, barely six weeks after being appointed, and threatened to launch a proxy fight to get the board replaced.

The company ultimately caved to shareholder pressure. With a new management at the helm, more changes may be in store for St. Joe.

Berkowitz told Reuters Sunday that he does not intend to take the company private but was willing to explore every alternative. He plans to replace high-cost professionals with low-cost managers to oversee assets and also plans to cut legal expenses arising out of lawsuits against Halliburton ( HAL) and two other companies over the Gulf of Mexico oil spill.

St. Joe has been under increased scrutiny since October 2010, when hedge fund manager David Einhorn said in a presentation that the company should take more write-downs and that he was short the stock.

Berkowitz told Bloomberg said he doesn't expect any changes to financial statements in the annual report released March 2 by Greene and the previous board.

"It's clean," he said. "Do you think the auditors would allow any sort of liberal policies given the stink about valuations?"

Sears Holdings

Lou D' Ambrosio, newly appointed CEO of Sears Holdings

Sears Holdings ( SHLD) announced on February 24 the appointment of Lou D' Ambrosio as CEO and president of the company.

The struggling retailer has been without a permanent CEO for three years, with W. Bruce Johnson serving as interim CEO.

Sears seems keen on shaking things up. Its new CEO comes from a background completely unrelated to retail. D'Ambrosio, who has an MBA from Harvard Business School, was previously CEO of Avaya, a Fortune 500 global telecommunications and technology firm.

D'Ambrosio ran Avaya between 2006 and 2008 and was instrumental in taking it private through a $8.3 billion private equity transaction. Before Avaya, D' Ambrosio spent 16 years at IBM.

Some sections of the market might question Sears' latest move in bringing in someone with experience in the technology field to run a flailing retail operation. But Sears appears to have actively sought out someone with D'Ambrosio's experience.

"From the beginning of our CEO search, we were determined to find a leader with information and technology experience who could catalyze the transformation of our portfolio of businesses in the context of the evolution of the retail industry that is occurring more broadly." Chairman of Sears' board Edward Lampert said. "Having worked closely with Lou and observing his business acumen, compelling leadership style, performance orientation and customer first approach, I am confident that Lou is the right person to lead and transform Sears Holdings."

Apple

Steve Jobs, founder and CEO, Apple

Management and succession issues have become a concern for investors of Apple after CEO Steve Jobs said in early January that he was taking a medical leave of absence until June. COO Tim Cook has been put in charge of operations while Jobs is on leave.

The CEO did not disclose his medical condition. But the state of his health and its impact on the company's future has been heavily debated in recent years. In 2004, Jobs was treated for pancreatic cancer. In early 2009, he had a liver transplant.

The announcement came a day before Apple announced another blow-out quarter. In a sign of confidence in the long-term story of Apple and perhaps some respect for the CEO's privacy, analysts refrained from quizzing management about Jobs' health.

Still, the familiar debate of whether Apple can survive without its main innovator did its rounds in the media. Some argued that Apple managed just fine under Cook the last time Jobs took medical leave, a period of 6 months. Others worried that the company's silence on a succession plan cast a shadow of doubt on its long-term prospects.

>>What Investors Can Expect From Apple's Cook?

According to a recent Wall Street Journal report citing anonymous sources, Jobs has been staying closely involved with the strategic decisions of the company, taking business meetings and calls at home.

>>5 Signs Steve Jobs' Absence Matters

While shareholders remain concerned about Jobs' health, they rejected a recent proposal that would require Apple to adopt a detailed succession plan.

The Central Laborers' Pension Fund wanted directors to issue an annual report on the CEO succession plan, review it yearly, develop criteria for the CEO and identify internal candidates. Apple had urged shareholders to reject the proposal, saying that it had a succession plan in place but that revealing it would give its rivals an unfair advantage.

AMD

Dirk Meyer, former CEO, AMD

Advanced Micro Devices ( AMD - Get Report) has seen more top-level executives depart the company after its board showed former CEO Dirk Meyer the door in early January.

On February 9, the company said that Chief Operating and Administrative Officer Bob Rivet and Senior Vice President of Corporate Strategy Marty Seyer are both stepping down to pursue new opportunities.

Their exits come as AMD still searches for a CEO to replace Meyer, who had run the company for two and a half years.

On January 10, 2011, AMD announced that its board had appointed Senior Vice President and CFO Thomas Seifert as interim CEO following the resignation of Meyer as president, CEO and a director of the company.

"Dirk became CEO during difficult times. He successfully stabilized AMD while simultaneously concluding strategic initiatives including the launch of GlobalFoundries, the successful settlement of our litigation with Intel and delivering Fusion APUs to the market," said Bruce Claflin, chairman of the board.

"However, the Board believes we have the opportunity to create increased shareholder value over time. This will require the company to have significant growth, establish market leadership and generate superior financial returns. We believe a change in leadership at this time will accelerate the company's ability to accomplish these objectives," Claflin said.

According to media reports, Meyer had been replaced owing to disagreements with the board over the company's mobile phone market strategy. Meyer had previously stated that while the smartphone and tablet market was a vast market, the company will hold off on investing in microprocessors for that segment as revenue opportunities were still small relative to the PC market.

Wells Fargo

Howard Atkins, former CFO, Wells Fargo

Wells Fargo ( WFC - Get Report) announced on February 8 that its chief financial officer, Howard Atkins was retiring from the firm immediately, to be replaced by Chief Administrative Officer Tim Sloan. Atkins will be on unpaid leave till August, when his retirement will take effect.

The bank said that Atkins was retiring for personal reasons and that his retirement was unrelated to the financial condition or financial reports of Wells Fargo. Atkins did not make a personal statement about his retirement.

The sudden announcement took investors by surprise as Atkins had often been the face of the company at investor and media conferences. The stock fell nearly 3% following the announcement, as markets speculated about the reasons for his move. Wells Fargo has not been known to make sudden management changes in the past. Investors were also worried about the impact the transition will have on the bank.

Atkins has been with Wells Fargo for 10 years, while Sloan has served at the bank for 23 years.

"In our view, Atkins is one of the top CFOs in banking, and is a very effective communicator of Wells Fargo's strategy and we view his exit as a very big loss for Wells Fargo," Citi analyst Keith Horowitz said in a note the day after the announcement.

Morgan Stanley analyst Betsy Graseck called the move "unexpected," in a note published Wednesday, but added that "it does not change our view on the stock, given Wells Fargo's deep bench."

J.C. Penney

William Ackman, Pershing Square Capital

J.C. Penney ( JCP - Get Report) announced on January 24 the appointment of activist investors William Ackman of Pershing Square and Steve Roth of Vornado Realty to its board, bringing the total number of directors to 13.

In October, Ackman and Roth disclosed a 16.5% and 9.9% stake respectively in the company. Ackman said the stock was undervalued and that he intended to have talks with management.

That prompted the retailer to invoke a "poison pill" to thwart a hostile takeover of the company.

However, the company appears to have reconsidered its options with the appointment of both investors to its board, suggesting that the management may be more willing to take the advice of its biggest shareholders.

J.C. Penney also announced plans for restructuring its operations, including shutting down underperforming stores, winding down its catalog and outlet operations and streamlining its call center operations.

Citigroup

John Havens, COO, Citigroup

Citigroup CEO Vikram Pandit on January 19 announced a major management overhaul as the bank seeks to meet new priorities as it expands into emerging markets.

John Havens, 54 and CEO of Citi's Insitutional Clients Group, was promoted to President and Chief Operating Officer of Citigroup. He will oversee the day-to-day operations and report directly to Pandit.

In addition, James A Foerse, the co-head of global markets will become CEO of Securities and Banking. Citi Vice-Chairman Ned Kelly will assume the role of chairman of the institutional clients group. Also reporting to Havens is Francesco Vanni d'Archirafi CEO of Global Transaction Services, regional CEOs of Europe, the Middle East and Africa, the regional CEOs of Asia Pacific, and the heads of certain global functions.

The appointment of Havens would cut down the number of people reporting directly to Pandit.

Havens is considered a close aide of Pandit. The executives have worked together for 25 years since their days at Morgan Stanley ( MS). Both joined Citi in 2007, when their hedge fund Old Lane LP was acquired by the bank.

Havens, Manuel Medina-Mora, CEO of consumer banking; Mike Corbat, who oversees the noncore Citi Holdings division; Chief Risk Officer Brian Leach; General Counsel Michael Helfer; Citibank CEO Gene McQuade; and CFO John Gerspach will continue to report directly to Pandit.

Google

From left: Larry Page, newly appointed CEO and Eric Schmidt, Executive Chairman

Google ( GOOG - Get Report) surprised investors when they announced results in January 2011, but it wasn't a mere case of beating earnings estimates.

In what it described as an attempt to simplify management structure and speed up decision making, Google announced that Larry Page, co-founder of the company, will take over the reins of Chief Executive Officer from Eric Schmidt, who had operated in that role for 10 years. Schmidt would assume the role of Executive Chairman, focusing on deals, partnerships, relationships and government outreach. The change goes into effect on April 4, 2011.

Industry observers saw Google's appointment of Page as CEO as an attempt to breathe back entrepreneurial spirit into the search giant as it faces rising competition from social media networks including Mark Zuckerberg's Facebook. Some expressed doubts about Page's abilities as CEO, as Schmidt has been seen as the man calling the shots over the last decade.

At a press conference at the World Economic Forum at Davos, Schmidt defended Page's credentials as CEO. "When people criticize Larry as the new CEO, that's grossly unfair to Larry," he said. "He has been with me at every business decision for 10 years."

If the announcement of the change triggered expectations that Schmidt would soon exit the company, his latest compensation package gave the Twitterati some cause to pause. Schmidt was awarded $100 million in stocks and options with a four-year vesting period, meaning he would have to wait at least till 2015 to fully cash out.

Hewlett Packard

Meg Whitman, former eBay CEO, joins the board of Hewlett Packard

Hewlett Packard ( HPQ - Get Report) announced a major shakeup to its board in early January, just a few months after the controversial exit of former CEO Mark Hurd.

The board of directors appointed five new directors, effective January 21. The new directors are Shumeet Banerji, chief executive officer of Booz & Company; Gary Reiner, former chief information officer of General Electric ( GE) and a current special advisor to private equity firm General Atlantic; Patricia Russo, former chief executive officer of Alcatel-Lucent ( ALU); Dominique Senequier, chief executive officer of AXA Private Equity; and Meg Whitman, former president and chief executive officer of eBay ( EBAY).

It also announced that four of its current directors will be stepping down in March -- Joel Hyatt, John Joyce, Robert Ryan and Lucille Salhany.

The market saw the board turnover as yet another attempt by HP to clean up management under its new CEO Leo Apotheker.

According to a Wall Street Journal report, two of the departing board members, Joyce and Hyatt, were strong supporters of Hurd, while the other two oversaw an investigation into the former CEO's conduct.

In August 2010, HP announced the departure of Mark Hurd following an investigation of the facts and circumstances surrounding a sexual harassment claim against Hurd and HP by a former contractor. HP said that the investigation determined there was no violation of HP's sexual harassment policy, but did find violations of its "Standards of Business Conduct."

HP's board came under harsh criticism for forcing the resignation of Hurd, who was credited for successfully reviving the company under his helm. Others criticized the board for sending Hurd out with a hefty compensation package, valued at $35 million at that time.

--Written by Shanthi Bharatwaj in New York

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