While you may get to play as the twisted Joker on PS3, he'll only be available on the game's Challenge Maps after you freely download him from PSN.
It's not confirmed either way if the Xbox 360 will be getting its own exclusive character, The Joker may have been a one-off deal with Sony. Arkham Asylum arrives this coming June.
Are you a fan of all this exclusivity when it comes to extra content? Batman: Arkham Asylum will be needing to elbow out some other big hitters this June when it arrives on Xbox 360, PS3 and PC.