I'm not the biggest Iron M an fan in the world but I have read the comics, as well as the comics for X-Man, Spidey, Avengers, FF, etc.
This movie was the best so far, and I didn't even go in sceptical, I assumed that it would be a great movie... Robert Downy Jr. was BORN to play the role of Tony Stark. I think the casting was spot on for all my beloved characters from the Iron Man series and I can't wait for future episodes in the Iron Man saga... just make sit through the entire credits reel you'll find the wait is worth it!
I'll be seeing this movie a second time on Saturday... it was THAT good... the only other Marvel movie I've seen twice in the theater was SpiderMan.