"The Dark Knight", as expected, is very good and is considerably better than "Batman Begins".
As we've all already heard, Heath Ledger was great as the Joker. Actually, all 3 of the live-action Jokers have been amazing (Romero, Nicholson and now Ledger). Ledger's is just a bit different than the other two. He's much darker and doesn't audibly sound like the prior editions, but he's amazing in his own right.
It's a little early to say that Ledger deserves the Oscar nod, but if he does get the nomination (I imagine it would be for Best Supporting Actor), I think he lands it in the interrogation room at the station. It's the best, most intense scene in the movie.
Much like Brandon Lee as The Crow, Ledger left us with a defining performance that we'll appreciate and enjoy for many years to come.
While The Joker is certainly a highlight of the film, Harvey Dent is no slouch either. I'm not even a big Aaron Eckhart fan, but he really does a great job in his role as well. For the first half of the film, he's actually the most dominant and interesting character.
"The Dark Knight" reminded me a little of the "Lord of the Rings: Return of the King" in that it felt like there were several endings during the film. Unlike LOTR, it wasn't a bad thing. There were several moments where you feel like you might be seeing the resolution to the story only to discover that things aren't as resolved as they seem to be.
Oh, and it's too bad Maggie Gyllenhaal wasn't in the original film; she's soooo much better than Katie Holmes.
Anyhow, The Dark Knight is a winner. Big shock, right?