Is Robert Downey Jr's second turn in the Iron Man armor as fun and entertaining as the first film? Probably not. Is it worth seeing if you enjoyed the first film? Probably, yes. 

Iron Man 2 suffers from a fair amount of sequel fatigue - too many characters, too many sub plots, and a little too much time spent setting up the upcoming Avengers film. While the first film let Downey's Tony Stark steal the show, this second outing seems to introduce too many over-the-top characters and not enough straight-men. Don't get me wrong, Downey still has immeasurable chemistry with Gwyneth Paltrow and Don Cheadle takes over well from Terrence Howard as Colonel Rhodes. It's more that the introduction of Sam Rockwell as Stark competitor Justin Hammer and Mickey Rourke as villain Whiplash/Ivan Vanko do not work nearly as well.

Rockwell's hammer is sort of a mirror Tony Stark, only not nearly as cool. While I realize his character is supposed to be irritating, it felt like a misuse of an otherwise fantastic actor. Likewise, Mickey Rourke never comes off as a truly threatening villain. Perhaps it's the fact that we're operating in a post-Dark Knight world, but I expect to feel some level of menace from a supervillian. Rourke's Whiplash is given a thinly described motive for revenge against the Stark family and Hammer's main focus is securing defense contracts. The film has some moments of great character work, however the pacing suffers from some lengthy scenes between Rourke and Rockwell.

Additionally, the film only offers three major action scenes - and while satisfying - the film might have been better paced with a little more suspense and action and a little less exposition. The final battle seems over a bit too quickly and plays very much as a ramped up copy of the War Monger fight from the first film. 

Despite these flaws, Iron Man 2 is still a worthwhile action film and a cut above most popcorn fare. The action scenes (limited as they are) are fun and offer the same high-tech superhero fun as the first film. Robert Downey Jr. is still the perfect person to play Tony Stark and it's hard not to get some fanboy chills each time he dons the red and gold suit. There are some fun nods to the expanded Marvel universe, including an entertaining, if not a little on-the-nose reference to the upcoming Captain America film. If you had fun with the first film, Iron Man 2 is a good way to spend an evening, but don't expect it to feel as fresh and original as it did before.