Fireworks explode over Washington as the United States celebrates its 234th birthday, Sunday, July 4, 2010. Seen from left is the U.S. Capitol, Washington Monument and Lincoln Memorial. (AP Photo/Cliff Owen)
Chase Miller, 10, and Ethan Kemp, 11, center from left, high-five passing veterans at the Huntington Beach Fourth of July Parade on Sunday, July 4, 2010, in Huntington Beach, Calif. (AP Photo/Adam Lau)
A 1936 Ford Cabriolet, foreground and a 1929 Bugatti Type 2 racer, left, participate in a Fourth of July parade in Key Biscayne, Fla., Sunday, July 4, 2010. (AP Photo/Wilfredo Lee)
ASSOCIATED PRESS Washington Nationals right fielder Michael Morse chases after a single by New York Mets' David Wright during the fourth inning of a baseball game in Washington, Sunday, July 4, 2010.
ASSOCIATED PRESS Baltimore Orioles' Adam Jones, left, scores as Boston Red Sox's Gustavo Molina waits for the throw on a single by Orioles' Scott Moore in the fourth inning of a baseball game, Sunday, July 4, 2010, in Boston.
ASSOCIATED PRESS Rafael Nadal bites the trophy, after defeating Tomas Berdych in the men's singles final on the Centre Court at the All England Lawn Tennis Championships at Wimbledon, Sunday, July 4, 2010.
Spain's David Villa, right, scores a goal during the World Cup quarterfinal soccer match between Paraguay and Spain at Ellis Park Stadium in Johannesburg, South Africa, Saturday, July 3, 2010. (AP Photo/Ivan Sekretarev)
Germany's Miroslav Klose celebrates after scoring the second goal during the World Cup quarterfinal soccer match between Argentina and Germany at the Green Point stadium in Cape Town, South Africa, Saturday, July 3, 2010. (AP Photo/Matt Dunham)
Serena Williams of the United States celebrates a point win over Russia's Vera Zvonareva during their women's singles final at the All England Lawn Tennis Championships at Wimbledon, Saturday, July 3, 2010. (AP Photo/Alastair Grant)
Uruguay's Diego Forlan celebrates after scoring a goal during the World Cup quarterfinal soccer match between Uruguay and Ghana at Soccer City in Johannesburg, South Africa, Friday, July 2, 2010. (AP Photo/Ivan Sekretarev)
Adili Wuxor walks a tightrope during the last day of his two-month tightrope walking performance on top of China's National Stadium, also known as the Bird's Nest, in Beijing Friday, July 2, 2010. Mr. Adili, an Uighur ethnic Dawaz tightrope walking performer, has been walking the tightrope five hours a day on the top of the Bird's Nest over the past 60 days, setting a new Guinness World Record. (AP Photo/Alexander F. Yuan)
Adili Wuxor lies on a tightrope during the last day of his two-month tightrope walking performance on top of China's National Stadium, also known as the Bird's Nest, in Beijing Friday, July 2, 2010. Mr. Adili, an Uighur ethnic Dawaz tightrope walking performer, has been walking the tightrope five hours a day on the top of the Bird's Nest over the past 60 days, setting a new Guinness World Record. (AP Photo/Alexander F. Yuan)
Adili Wuxor walks a tightrope during the last day of his two-month tightrope walking performance on top of China's National Stadium, also known as the Bird's Nest, in Beijing Friday, July 2, 2010. Mr. Adili, an Uighur ethnic Dawaz tightrope walking performer, has been walking the tightrope five hours a day on the top of the Bird's Nest over the past 60 days, setting a new Guinness World Record. (AP Photo/Alexander F. Yuan)
Adili Wuxor lies on a tightrope during the last day of his two-month tightrope walking performance on top of China's National Stadium, also known as the Bird's Nest, in Beijing Friday, July 2, 2010. Mr. Adili, an Uighur ethnic Dawaz tightrope walking performer, has been walking the tightrope five hours a day on the top of the Bird's Nest over the past 60 days, setting a new Guinness World Record. (AP Photo/Alexander F. Yuan)
Adili Wuxor waves a Chinese national flag while being lowered to the ground after his two-month tightrope walking performance on top of China's National Stadium, also known as the Bird's Nest, in Beijing Friday, July 2, 2010. Mr. Adili, a Uighur ethnic Dawaz tightrope walking performer, has been walking the tightrope five hours a day on the top of the Bird's Nest over the past 60 days, setting a new Guinness World Record. (AP Photo/Alexander F. Yuan)
Netherlands goalkeeper Maarten Stekelenburg makes a save during the World Cup quarterfinal soccer match between the Netherlands and Brazil at Nelson Mandela Bay Stadium in Port Elizabeth, South Africa, Friday, July 2, 2010. (AP Photo/Andre Penner)
President Obama is presented with a team jersey from the Women's Professional Soccer Champions Sky Blue FC, Thursday, July 1, 2010, in the East Room of the White House in Washington, to honor their 2009 season and for winning the inaugural Women's Professional Soccer championship. Team captain Christie Rampone is pictured seated left. (AP Photo/Charles Dharapak)
ASSOCIATED PRESS Oakland Athletics' Daric Barton, bottom, is out at second as Baltimore Orioles second baseman Scott Moore completes the double play on a ground ball hit by Kevin Kouzmanoff in the third inning of a baseball game Thursday, July 1, 2010, in Baltimore.
ASSOCIATED PRESS Serena Williams acknowledges the crowd, after defeating Petra Kvitova of the Czech Republic in their women's singles semifinal on the Centre Court at the All England Lawn Tennis Championships at Wimbledon, Thursday, July 1, 2010.