Rocksteady is in a really tough position when it comes to how to treat the Harley Quinn character. What I think a lot of people don't realize is that while all the other DC characters had to be given the toon treatment for Batman: TAS, Harley is an original creation from that series. Everything people like about the character comes from a very goofy universe, all things considered. Even though she's a character that crossed over into the comics, DC themselves have never been sure exactly what to do with her.
There are plenty of reasons why I think the fans largely rejected her in Arkham Asylum it was largely because it was too dramatic of a leap. The gimmicky outfit, the roided-up figure and the same, tiny voice all combined into an image that was not consistent with the character. I think the Arkham City design is a lot more on the nose, considering the universe it takes place in, but I think it'd be a lot worse if she was running around in the jester costume.
I still have issues with it (the corset screams "a dude designed my outfit"), but I think it's a lot better. Harley drama aside, I have nothing but faith in Rocksteady for this game.
YES.