U.S. swimmer Michael Phelps insists these will be his last games. The 14-time gold medalist will go out with a bang, aiming to claim the unofficial title of greatest Olympian ever from Soviet gymnast Larisa Latynina. She got 18 medals. Phelps has 16, and seven opportunities in London to overtake her. His rivalry with U.S. teammate Ryan Lochte promises one of the most compelling dramas of London. They will swim against each other twice: in medleys over 200 meters and, on the first full day of competition Saturday, over 400 meters in the Aquatics Center with its ceiling that slopes like the underbelly of a whale.
Jamaican sprinter Usain Bolt, the other standout star from Beijing, wants to become a sports legend on a par with Jesse Owens, Pele or Muhammad Ali by retaining his Olympic titles in the 100, 200 and sprint relay. But the World's Fastest Man faces stiffer competition this time from countryman Yohan Blake and American rivals Tyson Gay and Justin Gatlin.
In Beijing, the geopolitical significance of China's rise as a global superpower was as much the story as the sports. London, the first city to host the event a third time after previous games in 1908 and 1948, could in contrast be a purer Olympics, more about the athletes than the context. Could be more fun, too, without the backdrop of international concern over China's human rights record.
Big questions are how London's transport system will cope with millions of spectators and whether grumbling Britons will get behind their Olympics as they did for this year's celebrations of Queen Elizabeth II's Diamond Jubilee. The monarch will officially open the games at Friday's ceremony that will start at 9 p.m. with the sound of a 27-ton bell forged at the 442-year-old Whitechapel Bell Foundry, which made London's Big Ben and Philadelphia's Liberty Bell.
Lavishing more than 9 billion pounds ($14 billion), triple the estimated cost when London secured the games in 2005, in the midst of severe economic storms in Britain and Europe has provoked pointed and persistent questions about whether the expense can be justified and whether the games will have a lasting positive impact for the host city and for Britain.
The most obvious legacy for London is Olympic Park, with the 80,000-capacity stadium that will host the opening ceremony and other new venues. It is built on formerly derelict, polluted industrial land in the east of the city that bore the brunt of bombing in World War II and, for centuries, concentrated London's stinkiest industries and its poor.
Other benefits from the July 27-Aug. 12 games, particularly the power of the Olympics to inspire kids to take up sports and to aim high, might not be obvious for years.
John Leicester is an international sports columnist for The Associated Press. Write to him at jleicester(at)ap.org or follow him at http://twitter.com/johnleicester