Obama had some of the most interesting moments. He initially flubbed a "gotcha" question about America's "three top allies," and didn't mention Israel, but nicely handled the follow-up. He was more specific about health care than in past debates. And he did a solid job of answering questions about his position on Iraq.
Oh, my! A top three allies question. The UK and Canada are, I think, our numbers one and two allies. Apparently, the "right" answer is that Israel belongs in the top three as well. Seeing as how US troops have never fought alongside the IDF and we don't have a formal treaty commitment to the defense of Israel (we surely would have one were Israel to have defined borders, but it doesn't, so we don't) this strikes me as a difficult case to make. Australia is probably most aligned with us in foreign policy terms. But I think you'd have to say that the US-Japanese alliance has a hard-to-beat combination of closeness and strategic significance. The fact that NATO involves so many players, however, makes this a bit hard to answer, since that makes a whole big raft of countries very significant allies of ours.