Bump with a definitive answer- you get to see Moon Bloodgood's tits in the director's cut, in a scene that I remember McG mentioning he shot but removed from the theatrical version.
Completely retarded scene (it's supposed to sell the viewer on Marcus' humanity), utterly pointless and stupid, I can see why he realized he'd be dumb as toast to be willing to take an R rating for that scene and a slight bump up in gore.
edit: and having watched this again, I'm at the point where I think it's enjoyable as an action movie, but trying to devote any thought process at all to the plot of the story arc is completely counterproductive. Plot holes the size of trucks within the one movie, more like the size of cruise ships across multiple movies, as have been mentioned. But the action scenes themselves are fun enough, at least.
And hey, Moon Bloodgood's tits are rather, rather nice.