Hugh Hewitt is keeping a question by question scorecard of the debate.
Michelle Malkin is also live blogging the debate, as is Ann Althouse.
My impression is that Obama is "winning" the debate in the sense of speaking well the sort of talk that will appeal to undecided / uninformed voters. But that's just a guess. It's very hard for me to get into the head of these people who typically don't know much, usually don't care much, and often don't much know what to think on any given day.
UPDATE: My wife calls it in favor of McCain on substance. She's discounts the importance of style.
Final thought? He was so far in the tank that Tom Brokaw was growing gills.
UPDATE II: John Hinderaker -- "On the whole, [Obama's] a plausible rogue and I suspect that he passed muster with most people who aren't knowledgeable about the issues."