I'd agree with all of that —*I don't think the affair should rule Edwards out, but apparently does. (I'd ruled him out for other reasons anyway.) As you say, Hillary just doesn't fit as a VP, and Romney doesn't seem to fit as McCain's either.

McCain-Giuliani sounds plausible, helping with the economic credentials I think, but not shoring up support on the right; on the other hand, perhaps against Obama, that's less of an issue — and the extra votes it should pull from moderates could more than make up for that. Obama isn't half the centrist McCain is, and I can't imagine his running mate making up that deficit either.