The only two polls out today are the national trackers, and each of them show the race holding steady. Barack Obama maintains an 8-point lead in the Gallup Tracker, and a 4-point lead in Rasmussen's tracking poll.
Today's tracking polls removed interviews from Tuesday -- when voters had had the chance to listen to Michelle Obama's speech from the DNC but little else -- and replaced them with interviews from Friday, when voters could react to the entirety of the DNC, including Barack Obama's speech, but could also react to the selection of Sarah Palin as John McCain's running mate. Our model adjusts for the convention bounce; it does not attempt to correct for the VP bounce, even though there often is one (Joe Biden was an exception).
Since Obama's speech was well received by voters, one can probably assume that his numbers would be slightly higher had John McCain not announced his VP yesterday. On the other hand, the notion that something was gained by limiting Obama's bounce is silly. The convention bounce almost always fades by itself (it would more aptly be described as a convention 'bubble'). Stopping a bounce is a strategy designed to improve one's standing in the FiveThirtyEight.com polling averages for a day or two, rather than one's chances of actually winning the election.