Twenty-one-year-old Usain Bolt of Jamaica easily broke his own world record in the 100 meters to win the Olympic gold medal Saturday, slowing up to celebrate and still finishing in 9.69 seconds. Bolt stretched his arms out wide and put his palms out, then slapped his chest just before crossing the line. He came in well below his old mark of 9.72 seconds, set May 31 in New York - less than a year after Bolt took up the dash. What had been billed as a showdown was not close at all. Richard Thompson of Trinidad and Tobago took the silver medal in 9.89, and Walter Dix of the United States was third in 9.91. Bolt's specialty has been the 200, which he will be a heavy favorite to win next week in what would be first men's Olympic sprint double since Carl Lewis in 1988.