Updated from 12:23 p.m. EDT

Yeah, baby!

Caesars Entertainment

(CZR) - Get Report

is betting big on U.K. gambling deregulation, announcing joint-venture plans for a flashy $600 million gambling and entertainment complex next to London's Wembley Stadium.

Caesars will work with U.K. property company Quintain Estates & Development to build a 13-acre resort including a 400-room hotel and a casino with 135 gaming tables and 1,250 slot machines, along with shops and convention rooms. The partners will each own a 50% stake of the resort, which will be part of a 58-acre redevelopment area surrounding the stadium.

Caesars joins other U.S. gaming companies in launching plans to establish English beachheads.

MGM Mirage

( MGG) has been especially aggressive, announcing in April it would team up with Peel Holdings PLC to develop gambling and entertainment complexes in four U.K. cities: Liverpool, Manchester, Salford and Glasgow. That followed an announcement in February that MGM Mirage and the

British Land Co.

would spend between $364 million and $455 million on an entertainment and casino complex next to the Meadowhall Shopping Centre in Sheffield, England. The company has also purchased Wembley, a U.K. gaming firm that owns greyhound tracks in Wimbledon, Manchester, Birmingham, Oxford and Portsmouth.

Harrah's Entertainment

( HET) -- which in July inked a still-pending deal to acquire Caesars -- last year announced plans to develop eight regional casinos throughout the U.K. in a 50-50 joint venture with Gala Group.

Noting the plan is contingent on legislation and local approvals, a Caesars spokesman said "a best guess" would be for the casino resort to open in the second half of 2008. He added that in the deal, Quintain would put up the land, while Caesars would put up cash roughly equal to the land's value. The rest of the development would be financed either with existing lines of credit or debt instruments, he said.

Like other gaming companies, Caesars noted its planned resort's fate hinges on deregulation of U.K. gaming laws. Changes have been debated since 2001, but analysts have predicted a bill could finally pass into law this coming spring, paving the way for the construction of large casinos all over the U.K. A major variable remains taxation of casino revenue; British lawmakers want gambling to bolster government coffers as well as the gaming companies.

"You don't know what the gaming tax rate is going to be, and that's key to coming up with the earnings contribution" for Caesar's joint venture, said Joseph Greff, an analyst at Fulcrum Global Partners LLC in New York. A very rough estimate for the cash return on Caesar's $300 million investment -- its stake in the $600 million deal -- might be around 15%, Greff ventured.

The analyst expects Parliament to introduce a gambling deregulation bill this month and predicts passage next spring.

"How we look at the U.K. is 3% of adults have gambled there, vs. about 35% in the U.S.," he said. "We think there's a large target market that's fairly rich. Right now, gaming in the U.K. is different from the U.S. in that there are small betting parlors where you have to be a member, and there are no non-gaming amenities."

The news failed to lift shares of Caesars, which were down 9 cents, or 0.5%, to $16.95. The company plans to report third-quarter results Oct. 21. The average Wall Street analyst estimate is for earnings of 20 cents a share. MGM Mirage stock was down 6 cents, or 0.1%, to $51.41. It reports its third quarter Oct. 20, and analysts on average expect earnings of 57 cents a share. Harrah's shares were off 55 cents, or 1.05% to $54.10. Harrah's also plans its third-quarter release for Oct. 20, and the average estimate is for earnings of 88 cents a share.