Interesting...
I thought it was a good start, but like all flash videos, could use some touching up.
Here's some good stuff:
-The animation seemed choppy, but it flowed for the entire video, so it didn't draw away my attention. I liked it.
-Fans of the series knows who is who. The art wasn't bad.
Some (hopefully) helpful stuff:
-Some continuity errors with Two-Face. Sometimes his "Bad" face was on the left, sometimes on the right. Being a humongous fan of Two-Face, I can say that his "bad" side is always on the lef tside of his face.
-People who aren't fans aren't going to really know what's going on - maybe. There aren't any lines n' stuff, but I think that the heros/villains are suggested well enough.
All in all, good job.