I didn't like the film very much, starting with Gotham looking too modern and sleek rather than otherworldly or grim.
Batman hoping to be able to retire after a year made him feel too young and he often felt like a supporting character (a charge often made against Batman Returns
, and here the villains weren't interesting enough to make up for it).
The Joker was alright but not as good as he was hyped up to be; he could have used more dark humor to be more unique.
Batman taking responsibility for Dent's crimes was a good example of how short-thinking he was. There could be another public hero later but in order to preserve the image of one who died (I disagree that the truth, or at least ambiguity, would be so devastating to people), he gets the cops against him rather than continue to use their help. He also risks the public accepting murderous vigilantism if they accept him by making that part of his image.
I enjoyed Batman Returns
, Batman Begins
and Spider-Man 2
more, I thought they had better mood, character development and action.