I would say basketball or football
the world cup
Formula 1 Racing over 500 million viewers in 2010.
im guessing billions worldwide, its the most famous impactful event in tv history, almost everyone on the planet know the event
According to wikipedia, the sporting event with the largest TV audience worldwide is the FIFA World Cup, followed by the Summer Olympics. The Super Bowl is the biggest TV event period in the United States.
The most watched television network is CBS. CBS has over five million viewers. ABC is the next most watched network and then the Disney channel.
The most watched TV show in Britain is Coranation Street. Coronation!!
For most sporting events, there is always television to think of. The television broadcast will begin on the hour, the announcers will speak for a minute or two, there will be a minute or two of commercials, and the game will start between 5 and 7 minutes after the television broadcast begins. But where there is a sporting event that is not televised, it usually begins on the hour or half hour.
With over 3.5 billion fans, football (or soccer) is undeniably the most watched sport in the world. Football has the maximum stadiums, greatest numbers of people buying football merchandise, number of competitions and events held - such as the world cup, UEFA League, American Cup, etc. Also there are the maximum number of teams, leagues and clubs for football all over the world. The current football world cup 2010 has about 715.1 million people who watched the final. It is the world's most widely viewed sports event today.