Thompson is done. Huckabee will continue, but he's lost his viability (probably). McCain will get great media coverage out of tonight, but so far this has been a truly momentumless nomination contest and he surely can't count on a huge bounce coming into Florida.
If I were an oddsmaker, I think I would have to make McCain a slight favorite to win in Florida on January 29 over Romney and Giuliani, but no one should be much surprised if either of the latter two takes it. More on Florida as that race heats up next week.