Short version: I loved The Dark Knight despite its manipulative sadism.
Long version: The Dark Knight is everything a summer blockbuster movie should be. Plenty of violence, chase scenes, compelling story, long play time, over-the-top acting -- it has it all.
What I didn't like about the movie is that it was guilty of a couple of pet peeves of mine. One thing that bothers me in movies is when a movie preaches against something it's guilty of itself. The Count of Monte Cristo is a perfect example of this. On the surface, the movie supports the theme that revenge is bad. In the end, the guy loses his love because he's changed too much, etc. But on a deeper level, the movie (and book) is a celebration of violence. In fact, it has no value -- aesthetic or otherwise -- without using revenge as a driving manipulative force.
It's a neat trick. Not only do we get to revel in vengeance, but we also get to feel good about ourselves by climbing to the moral highground at the end.
The Dark Knight has some of that dissonance going on. There's all this lofty talk about the nature of heroism (or anti-heroism), but deep down, the movie relies on the joy of violence. In real life, violence is rarely both satisfying and warranted, unless it's done by a cop.
I know, I know. It's comic book violence. But there's something especially unsettling about the violence and torture when there's an attempt at sophistication. Any realistic depiction of that level of violence should be less gratifying.
Still, I dug it.