This is the launch trailer for Batman: Arkham City, out this week on 360 and PS3. It shows most of the people you fight with, and against, in the game.
I actually finished the game yesterday. The reason I bring this up is that I didn't see some of the content in this trailer, meaning it was part of a side-mission I never got around to completing. So, yeah, there's a lot of stuff to do!
PC owners, in case you're in the dark, your version won't be out until November. Sorry.