In a nutshell the movie is very well written. If you can get past the fact that Don Cheadle replaced Terrence Howard as Rohdey then you've gotten over the hard part.
Mickey Rorke makes a great villain and delivers a very cool and believable portrayal of Ivan Vanko.
The writers crammed a lot of information into a short time span, but they made it flow very well. With the introduction of Nick Fury and a better dip into S.H.E.I.L.D. that wets your appetite for a sequel or even possible off-shoot movies.
The CGI was well executed and not over used and the battle scenes and camera angles were very good. It didn't have that chopped up feel that some other movies get when there is a lot of computerized motion.
I recommend this to any Iron Man or Marvel Comics fan as well as anyone that just wants a good action flick to see.