I recently got a PS3 and Batman: Arkham City (BTW: Mark Hamil...think about it...).
And I really can't tell if the thugs on the street are getting tougher, or I'm getting crapper somehow.
I'm guessing they are getting tougher. In Arkham Asylum you had a semi linear tunnel, so you could tell that the further you go, the tougher it gets. Here - it feels like - I dunno, did that guy club me in the back of the head because I screwed up, or actually he's been set to a higher difficulty.
It's an odd flaw - ambiguity of difficulty. It'd be better to show the difficulty of the goons somehow.