I didn't realize pollution in Beijing is so severe that events might need to be postponed. It's so bad it could make it difficult for athletes to break world records at the 2008 games - I think this should be a factor in choosing future sites.

Quoted: Some events in the 2008 Summer Games may have to be postponed by a day or two if air pollution in Beijing is excessive, the International Olympic Committee said on Thursday. How will all this pollution affect the Olympic athletes?