ArkhamCity.co.uk: Here's a run down on everything that that has been announced for Batman: Arkham City.
--Thugs will have a much wider variety of appearance than in the first game
--Most thugs will be grouped into gangs, each headed by a staple Batman villain. Confirmed so far are Joker and Two-Face, with many more hinted
--You can keep track of the gangs in your criminal database
--Thugs not attached to a gang roam the streets
--Riddler thugs have replaced Riddler maps in the new game, and will require interrogation before they will talk
--Confirmed so far are Joker (Trailer), Harley Quinn (GameInformer), Two-Face (GameInformer), Talia Al’ Ghul (VA Confirmation), Mr. Freeze (VA Confirmation), and Calender Man (OXM) , with Black Mask and Penguin hinted at in the trailer.