Just watched this last night. Very cool movie. Stayed pretty true to the comics. Nice animation and good sound. I liked it much more than any of the Nolan Batman movies. Why is it that WB animation can regularly churn out stories that are more compelling than anything that comes out of Hollywood?
About the only bad things I can say about it was that I didn't like the voice of the guy playing the Joker. Mark Hammill is the voice of The Joker, period. Jensen Ackles as the Red Hood was pretty bad. It was like watching another episode of Supernatural. Sorry, but that guy cannot act. NPH was pretty cool as Nightwing. The guy playing Batman seemed to be doing an impression of Kevin Conroy and it was a pretty good one. He sounded a lot like Kevin Conroy.
Definitely worth a rental.