Noble Energy ( NBL) upgraded at Wells to Outperform, Wells Fargo said. Estimates also boosted, as the company is leveraged to higher energy prices. Overseas Shipholding Group ( OSG) upgraded at Credit Suisse to Outperform from Neutral. Valuation call, tanker market in midst of longest trough since 1990, Credit Suisse said. Price target increased to $33 from $30. Portland General ( POR) upgraded at Goldman to Buy. Company trades at a discount to its peers and consensus estimates could prove conservative. Pioneer Natural ( PXD) upgraded at Wells from Market Perform to Outperform, Wells Fargo said. Estimates also boosted, as the Permian Basin should continue to drive growth. Southern Union ( SUG) upgraded at Wells from Market Perform to Outperform, Wells Fargo said. LNG project could be a game-changer for the company. VMWare ( VMW) price target boosted at Credit Suisse to $70 from $60. Strong bookings in 1Q11 results, Credit Suisse said. Maintain Underperform rating. VMWare ( VMW) upgraded at Capstone to Hold, Capstone Investments said. $86 price target. Estimates also boosted, to reflect the company's new guidance. VMWare ( VMW) estimates, target boosted at Morgan Stanley. Shares of VMW now seen reaching $112, according to Morgan Stanley. Estimates also upped, given better license and billings growth. Overweight rating. Wisconsin Electric ( WEC) downgraded at Goldman to Neutral, Goldman Sachs said. Valuation call, as the company lacks near-term catalysts. Westar Energy ( WR) downgraded at Goldman to Sell, Goldman Sachs said. Company is facing increased regulatory risk. End of report.