Having read more reviews for this than any other movie, I have to say something explosive. Within the confines of mortal creatures telling a Christian story, The Dark Knight is a great Christian story, starring Batman as a type of Christ.
The Joker is the Devil. He tempts and loves destruction. Batman is not a hero, as Gary Oldman says, “he is the guardian and protector that we deserve.” Seems similar to we “we despised and rejected of man.” Batman does not rack up a body count, in fact he spends a lot of time arranging things for his followers the cops. I think that this could be stretched into a triune role of batman, coordinator, defender, inspiration. Or Lucius, the Butler, and Master Wayne. For all you paedos, notice that the children see and understand more than the adults do.
Batman takes the sin of Two-Face, the ultimate metaphor for sinful man upon himself. For that, he is justifiably pursued, Two-Faces sin cries out for judgement. Batman cannot die, but he can suffer pain, including the pain of exile and derision that was inflicted on Christ.
The only great sticking point that I see is Batman’s assertion that the Joker forgot about the basic good nature of the people. I would point out that if Batman is a type of Christ, and Gotham is his city, then his people are by definition taught what is right, and shown the way to do right.
This is all somewhat tongue in cheek, I know that it is not scripture. But it is some of the more thought provoking filmmaking that I have seen, and as such, it calls for interaction. Like Signs, it makes me think that there are either more Christians than we know in hollywood, or God can use even vessels of wrath to sound the note of truth.