Fwiw, over at Google News, the current wrap-up of headlines regarding last night's polls, suggests that more viewers thought Kerry did a better job last night.
A Reuters/Zogby poll, taken just before the debate, has Bush up one point, 46 to 45, over Kerry. Story here. Regardless of the exact number, it seems that whatever daylight that Bush opened up after the GOP convention seems to have gone gently into that good night. And that we'll be in for another very tight presidential race.
And, quite possibly, the fourth straight race in which the winner doesn't get a clear majority of the popular vote. That's unprecedented, at least in recent history. I'm not quite what the significance of it is, though I suspect that it suggests that for all the talk of "polarization" among the electorate, we actually are in an age of massive consensus about the role and scope of government (which, to my mind, is bad, given the size of the government).