Torrentfreak runs an article about the video streaming sites set up for the Olympics:
Interestingly enough, free and legal online streams are available in pretty much all parts of the world except the United States. YouTube, for example, is streaming all events in 64 countries across Asia and Africa including Afghanistan, Pakistan, Angola, Ivory Coast, Ethiopia and Zambia.
In the UK the BBC is offering a free online stream, and many other countries have their own alternatives.
The lack of free live streams in the U.S. is going to be one of the main reasons why people will pirate the 2012 Olympics.