There are certain staples, things you expect to see in every "superhero" movies: the convoluted Evil Plot; the villainous monologue; the long, continuous action scenes. If you don't like these things, find them boring or irritating, do us a favor: stay away from The Dark Knight.
Batman Begins was arguably the darkest of the genre, exploring duality of character, the underlying shadow of us all, and the lines we draw to keep ourselves sane. But if Batman Begins explored the line between genius and madness, The Dark Knight happily skips over that line and plunges into the frightening world of the cheerfully insane, the world of gleeful anarchy and flippantly horrific. Edgar Poe, Alfred Hitchcock, and H.P. Lovecraft dipped into this world, and Stephen King and Clive Barker after them. The Dark Knight takes from those legacies and shows the (relatively realistic) manifestation of those ephemeral nightmares. And though the entire cast delivers stunning and compelling performances, really, it all hinges on the Joker.
There's been Oscar buzz about Heath Ledger's performance in this movie, and I admit, I thought it had to do with his tragic, untimely death. For that, I must sincerely apologize to Mr. Ledger's spirit, wherever he and it may be. Only upon a second viewing was I able to see Heath Ledger beneath the Joker, and even then only in parts and only with scrutiny. In no way, at no time, does the Joker walk, talk, or gesture like Ennis Del Mar or Jacob Grimm. Patrick Verona makes no appearance in this film. This portrayal of this character is entirely unique ... and bone-chillingly frightening. Though the Joker -- true to his name -- laughs throughout the film, dropping puns and paying homage to pop culture, the audience never joined in with anything heartier than a nervous chuckle. His was a brand of humor tinged with an unhealthy socio-pathology. Though his 'magic trick' was funny, no one laughed at it.
Yes, the movie runs on a little long. Yes, the plot is a little complicated. Yes, the villain(s) monologue and posture. Yes, Bruce and Batman -- and everyone else -- take a backseat to the Joker. Yes, this movie is too violent and too dark for young children (They really mean the "13" in PG-13).
None of those things matter. At the end of this film, you won't be talking about how long it was, or how much the evil minions talked, or how there was too much going on. You'll be chilled and wide-eyed with awe, breathlessly anticipating Christopher Nolan's next installment.