I really liked The social Network a lot. I tried to watch it with no expectations, and was very pleasantly described by the smart dialogue that grabs you right from the opening scene with Zuckerman bumbling his way into a biting rejection from the girl in the bar.
I have no problem with not seeing everyone in terms of black or white, "cookie-cutter morality", since I happen to think it's true that people are never all bad or all good anyway.
I have no idea how he is in real life, but the Zuckerman we saw portrayed in this movie had a serious emotional problem that was summed up pretty well in the comment made by the legal associate at the end: "You're not an asshole, Mark. You're just trying so hard to be."
I really enjoyed the movie. Made me think, in a bunch of different ways...