This is definitely one of the best Marvel Comic-turned-movie in some time. Lots of action, cool gadgets, and moments of awe.
Robert Downey Jr. is perfect as the pompous Tony Stark from scene 1. The first half of the movie gives the origins of Iron Man. And it just gets better hen he returns home to improve the Iron Man armor.
Make sure you stay until the very, VERY end of the movie - after ALL the credits have run, for a big, crazy surprise. And then you'll be asking yourself the same questions we were. When and how are all these Marvel Comics superheroes gonna cross paths. I mean, could you imagine one movie with Iron Man (Robert Downey, Jr.), Hulk (Edward Norton), Fantastic Four (ie, Jessica Alba), the X-men, Spiderman (No, not Tobey again), Captain America, Dr. Strange... do you see where this could go?!?