OK, here's my take with spoilers below. These are the things that stuck with me after seeing it:
Batman can make your cell phone invade your privacy and then beam it all back to his mask. Lucious Fox will find this offensive and threaten to quit.
If you damage the Batmobile, it'll explode and a motorcycle will pop out.
You can run the Batpod up the side of a building, but then you crash after missing the Joker.
Batman lost his grip and had plenty of time when he fell at the end of the movie, but chose not to glide down and fell on his ass instead.
The main villain was not the Joker, just some crazy guy with makeup on. Other than that, his biggest trick was planting barrels of gasoline with detonators attached.
Heath Ledger stole the show.
Christian Bale didn't work out much for this movie.
Harvey Dent will suddenly decide to go crazy and threaten people even without acid on his face- he'll just flip his shit and take one of the Joker's men and threaten him.
Christian Bale sounded very nasal in this movie- he did a better job of the voice in the first one. In the future, see if Michael Keaton will do a voice over because he's the only one to get it right so far.
The Batsuit looked crappy- I expected nipples.
Flame away, it's just my opinion.