I think The Dark Knight is a great big mess of a movie. Ledger and Eckhart were very good as The Joker and Two-Face, though, which goes a long way toward making it worthwhile.
Never even heard of Traitor.
Batman as a character was very underdeveloped in this movie, when compared to Joker/Two-Face. Then again, that's what Batman Begins was for. Overall, Ledger and Eckhart carried the movie, as it sure as hell wasn't Bale.
And sadly, the end left me wanting more of Harvey, and apparently as of right now, he's unconfirmed for the sequel.