Loved it. Definitely one of the best superhero movies ever. Better than the Spider-Man and X-Men trilogies combined. Downey made Tony Stark breathe better than anyone could, and I can't wait for the sequel.
By the way, did anybody catch the scene at the end of the credits with a certain actor who had to deal with motherfucking snakes on a motherfucking plane? I missed it, but I'll have to go see it again just for the extra scene. I read about it this morning and was geeking out to myself.