"In the new poll, taken Friday through Sunday, McCain leads Obama by 54%-44% among those seen as most likely to vote."
http://www.usatoday.com/news/politics/election2008/2008-09-07-poll_N.htm
Yep, and Obama got a huge push in the polls after the DNC too. The article itself says post-convention polls are useless...
However, in an analysis of the impact of political conventions since 1960, Sabato concluded that post-convention polls signal the election's outcome only about half the time. "You could flip a coin and be about as predictive," he says. "It is really surprising how quickly convention memories fade."
Considering that up until these conventions, this is only the 2nd time McCain has been ahead in the polls (and the first time was extremely brief, just as this time is expected to be), then anyone who thinks these polls are significant is kidding themself.