I did a wrap for it over at Plum Line. Short version: these candidates are awful. I was a little more cranky than usual, so you might or might not enjoy that.
My usual practice is that I watch the debate with twitter, so it's basically MST3K style -- which has it's advantages and disadvantages. But then when it's over, I don't look at anything until I've sent my wrap in to the Post; I figure that I pick up on the reactions of individual moments from my twitter feed, but I want to reach my own conclusions about the debate as a whole. At any rate, looking around now it looks as if the press consensus is that Rick Santorum did poorly. I can see that -- in fact, several of my examples of poor debate skills used Santorum. Still, two major cautions. One is that what matters in the first instance is how all of this looks to undecided Republican primary voters, and they live in a very different world than almost all of the people who are punditing about it tonight. Including, for that matter, many conservative yakkers. But the second thing is that what matters even more than the first reactions of those GOP voters is the reactions of conservative opinion leaders, because they're the ones who are going to pick which clips to play, and which quotes to repeat. At least, on the shows that those undecided voters watch and listen to.
In other words, I'll repeat again what I've said before. As far as picking winners and losers -- don't trust me, don't trust most pundits. Sure, sometimes it's obvious, such as Rick Perry's famous gaffe. But usually, the winner of the spin war wins the debate, and you need to watch Fox News and the other partisan media outlets to get a sense of that.