The Dark Knight = Awesome Sauce
Christopher Nolan = Awesome Sauce
Christian Bale = Welsh Awesome Sauce
Gary Oldman = Bulletproof Awesome Sauce
Maggie Gyllenhaal = Chipotle Awesome Sauce
Aaron Eckhart = Burned Awesome Sauce
Cillian Murphy = Surprise Awesome Sauce
Morgan Freeman = Chamomile Awesome Sauce (makes your voice smooth and silky)
Heath Ledger = Awesome Awesome Sauce
Quod erat demonstrandum
Seriously, the only potential flaw with The Dark Knight is Christian Bale's goofy "8-year-old trying to sound like an adult" deep voice when he's Batman. Well, that and Eric Roberts, but there's never any excuse to cast Eric Roberts, so he's kind of a mulligan. Other than that, the movie is one of the best films I've ever seen, and has probably moved into my Top 5 Movies of All-Time, and that's not really an easy list to crack.
Everything works. This movie definitely vaults Bale past Michael Keaton as the best Batman (Clooney and Kilmer? Please) ever.
Maggie Gyllenhaal is absolutely perfectly cast as Rachel Dawes, a casting choice which is made even more clever when contrasted against the casting of Katie Holmes - a far inferior actress - in the same role in Batman Begins.
Aaron Eckhart is brilliantly cast as Harvey Dent, drawing on his Sultan of Spin persona from Thank You For Smoking, and the makeup with him as Two-Face will make you completely forget about Tommy Lee Jones (thankfully).
Gary Oldman, Morgan Freeman, and Michael Caine reprise roles that helped to support Batman Begins; roles which they elevate further in this incarnation.
Then, there's Heath Ledger. What can you say? His death aside, this was a performance for the ages. Frankly, the fact that he passed away has probably overshadowed just how amazing of a performace it was. If he were still alive today, it would surely have still received just as much applause, and if not, a cinematic crime would have been committed. There is about a five-second span where he hearkens back to Jack Nicholson's portrayal in Batman, but other than that, the performance is entirely his own. He evokes fear as the viewer realizes that this character really is nuts just for the sake of being nuts.
"I'm just a wild dog chasing cars; if I actually caught one, I wouldn't know what to do with it."
That summarizes exactly what he brings to the role - a sense that The Joker really is acting out his lunacy minute-by-minute, planning out the ends of the deed, but ad libbing the means.
This movie really is everything that everyone says; there is no hyperbole and no exaggeration in any of the sparkling reviews it has received. That it has a 94% Fresh Rating and an average rating of 8.5/10 on Rotten Tomatoes speaks to its quality. Frankly, the fact that 12 out of 198 reviewers rated it lower than 3/5 seems like a surprisingly high statistic (I'm not actually certain this guy watched the same movie).1
So, see this movie. See this movie a couple of times. I'm not saying that because "You'll notice things you didn't see the first time" (who knows, you might, I'll find that out tonight), I'm saying that for the same reason you eat the same thing at a restaurant, or read a book more than once, or go to a certain vacation spot every year - it's that good.
1 - It also currently holds - with a 9.7/10 rating - the #1 position on IMDb's Top 250 List, but in that case, The Shawshank Redemption is the third-best movie ever, so take that list with a grain of salt.