And I won't compare it to TETSUO II: BODY HAMMER (although I'll point out Sam Rockwell's villain character is named Hammer, so maybe...)
Anyway, it's a fun, frantic action flick. If you're in the mood for summer action fun, Downey Jr. is still perfect as Tony Stark/Iron Man, and really hams it up well. Mickey Rourke equally so as the villain (and son of a Russian physicist who believes Stark's father stole the ARC idea from him, hence a really overdeveloped grudge). Sam Rockwell is excellent as always conniving business rival. Gwyneth Paltrow is still fine as Pepper Potts, and Don Cheadle is also great as Rhodey (and one of the few characters aside from Stark who's actually given an arc to follow). Gary Shandling makes a great turn as a Senator, Samuel L. Jackson is just keeping us warmed up for THE AVENGERS movie, and Scarlett Johansson isn't given enough to do. For that matter, neither is Samuel L. Jackson, and they sort of make the movie feel a little over-stuffed, but no matter. Oh yeah, and director Jon Favreau again gives himself the role of driver Happy Hogan and for some reason likes to show himself getting punched in the face many times. He's the comic relief.
Also, if you don't like big action movies but like pointing out plot holes, that's a second source of fun. Most egregious example is in Monaco, at the Grand Prix where Stark decides to drive his own car. Although all of his inner circle is surprised, and it appears to be a spur-of-the-moment decision, for some reason Ivan Vanko (Rourke) knows he was going to do it, had already snuck onto the track as part of a pit crew, and is waiting to attack Tony. Electricity whips are one thing, but his psychic powers are even greater. And that's just one example.
Running Time: 124 minutes
My Total Minutes: 185,273