Meh. It was okay.
I liked that they didn't kill any of the villains. In fact, I loved it as I hate it when the villain is killed in nearly every comic book movie (Magneto and Luthor being the two major exceptions).
The weaknesses of Batman Begins where done away with (as interesting as the backstory is, it was too long) while the everything it did right was amped up.
Not sure who is better, Ledger or Hamill, but they both nailed it perfectly.
Now I need to get some sleep for work... today.