I really enjoyed it. Good action, good story, some funny moments.
I've seen a few complaints here and there that Iron Man wasnt in it enough. The problem I have with that is that both this and the first film go out of their way to make it abundantely clear that Iron Man IS Tony Stark. So a film that features Tony Stark is a film that features Iron Man whether in suit or not. Was the suit itself seen enough in this film? Maybe, maybe not, but in my opinion, the appearance of the suit, or lack of it, doesnt detract from the film at all.