Soccer aka Football to the rest of the world, is the most watched and the most bet game across the planet. It is sick the amounts of money wager on this sport. More money is bet on the World Cup than any other event in the world. Sure worldwide, people watch the Olympics, they watch the Super Bowl, they might even watch the World Series (Hello Japan). But people don;t watch any single event more than they watch the Football World Cup.
Of course there are a few other World Cup's as well. There is the World Cup of Cricket, the World Cup of Rugby, the World Cup of Beer Pong, etc.
The next World Cup is in 2010 in South Africa. South Africa is at the bottom of Africa and produces a lot of Diamonds. They also have some great casinos there. I even think that online gambling is legal there, and they have a few online sportsbooks and casinos based in South Africa.
The 2014 World Cup will be held in Brazil. Land of the carnival, the real Madri Gras. Countries are currently submitting bids to try to host the 2018 World Cup.