Figured I'd bump this since closest we have to a Kick-Ass thread.
Just came back from checking out the movie, and it was good fun. It was one of the best comic book movies I've seen, and its full of life and is genuinely funny. I would say it features excessive language if you are against that.
It also had a terrific climax, one of the best final fights ever.
And loved the little cues to other comic book movies, the opening theme has hints of the SUperman theme, the driving theme has hints of the Batman theme, and the fighting theme has bits of Batman Begins. Nic Cage speaks like Adam West's Batman and the final line is straight from the original Batman movie.
Some of the things were changed from the comic book, but to me actually made the movie better than the comics IMO. On the same hand, didn't read it all in a while so may change my mind.
I say give the movie a watch. I will buy when it drops on Blu.