Definitely funny at points. Though I've found that, when a film is very tense, it's a lot easier to make the audience laugh, because they're actively looking for something to break the tension. So much of humor is circumstantial. Thus, while a man dressed up like a nurse isn't really all that funny by itself (unless you're a fan of Benny Hill or something), it becomes downright hysterical for some in The Dark Knight. It's funnier because there's more contrast between the film's baseline mood, and the joke itself. By making most of the film more serious, the comedy becomes more striking.
This doesn't always apply, of course. Some films are so deathly serious that humor would just feel out of place. But thankfully, The Dark Knight isn't that sort of film.
This doesn't always apply, of course. Some films are so deathly serious that humor would just feel out of place. But thankfully, The Dark Knight isn't that sort of film.