Best Buy Lists Playable Robin As Arkham City Preorder Bonus
According to this listing on Best Buy’s site, Robin will be featured as a playable character in Batman: Arkham City if you preorder the game with them. A screen-cap of the offer (showing certain details that were later removed) states that Robin will only be used in two challenge maps.
Not exactly the best preorder bonus, but… it’s an option. It’s definitely not going to be as significant as the PS3 Joker DLC for Arkham Asylum, but that’s probably for the best since it’s just a preorder bonus.