I haven't looked forward to a movie coming out this much since The Matrix 2 was coming to theaters.
I was pleasantly surprised by Iron Man and how well they told the story to someone that knew nothing about the comic book (me).
I thought it was better then SpiderMan... better then any of the super hero/comic book movies I've seen so far actually. I would put it on par with Transformers - I loved that movie as well.
Like all movies that will become the beginning of a series, there was a lot of story telling in this one - making room for more action in sequals. Speaking of that, make sure you stay through the end of the credits... ;)