Just want to share some thoughts.
I just played through the demo--
From what I have seen the graphics, voice-acting, and comic style cut-scenes are all pretty well done for a 'budget' title (especially from a dev called Deadline Games *wink). They are above what I expected, and the game (demo) runs flawlessly on my upper-mid PC.

Right away I can think of two things that would have elevated the game from C material to a solid B or B+:
1. Two player LAN or IP host/client games. I appreciate that they kept the split/screen mode over from the console version, but nobody plays that way on the PC. It can't be that hard, its the UNREAL (or is it?) engine, that's practically what its made for.
2. The AI pathfinding is a little bit screwy, enemies run around in circles sometimes, and once, when I was playing as Rorschach, Batman got stuck behind an open door and didn't get out for half of the level.
3. EUPHORIA (like GTA IV)-- I know its asking too much, but a game like this with so much pushing and throwing guys around is just screaming for it (and going up stairs would be cooler). Euphoria alone would bump this game up into near AAA status, I think. Barring something as complex as euphoria, better character collisions would be cool, I sometimes felt like I was sliding off of people.

Obviously the game was made on a short development cycle, to coincide with the movie release, and is meant to be more of a fun diversion. I didn't expect to be blown away, but I am impressed by the fact that the game actually seems to be pretty good. I hope the critics treat it fairly in the reviews.