Dark Knight

It was as good as Iron Man, maybe better, and I was blown away by Iron Man. Dark Knight might have the edge, since the villains and their subplots were so well done. Ledger was great, but I was impressed with the Harvey Dent subplot, as I was expecting it to be more of an afterthought, and it's integrated perfectly. I would say this would be one of the few comic book movies (the Spiderman series would be another candidate) that should definitely be seen even by people who don't like comic books, just for the excellence of acting and writing.