From BBC News:
An IOC inspection team said the Chinese capital was making “considerable progress” after a visit on Thursday. But it asked for more details on plans to improve air quality because of the smog that often hangs over the city.
“This is of the utmost importance to the athletes, who are the most important part of the Games,” said IOC official Hein Verbruggen. (We have requested) contingency plans, if needed, for the test events this year and also for 2008… (but) it is not totally clear what the effects will be.” [Full Text]