Usually when a movie is as hyped at The Dark Knight has been, the movie can't live up to expectation. This movie manages to surpass expectations.
That being said...this movie isn't for the faint of heart. The joker is truly disturbing, and the movie is DARK. Way darker than any previous Batman movie. I think they managed to capture the feeling of despair perfectly.
As an aside, I think that Maggie Gyllenhaal did a fantastic job replacing Katie Holmes, in fact, I wish that she had been Rachael in both movies...she adds much more depth to the character.