I responded in the comments section of the original question, but with the Batman films, it's essentially due to the blunt exposition and lack of subtext. In The Dark Knight, almost every major character explicitly describes his or her role in the film (e.g. "I am an agent of chaos."). If you didn't catch what was happening at the end, Commissioner Gordon explains it to his child. The only real reason to include this sort of exposition is if you think your audience is as clueless as Gordon's kid.
The characterization is fine, it's just shallow. You pretty much get everything you ever need to get out of any given character from what they say, which I find uninteresting as a viewer. Characters like the Joker also don't interest me very much. They fall into the category of "just plain ol' zany". The performances were very good, but I didn't enjoy the writing at all.
I enjoyed The Prestige a great deal despite the heavy exposition, in part because I felt the characters were easier to relate to. I liked Batman Begins well enough, but by the end of The Dark Knight, I was over the series.