Im really looking forward to playing this. It sounds really really good already
They have made alot of new cool improvements and left some of the original.
All of the gadgets and toys previously obtained in the first game will be present at the start of Arkham City, some have some improved, new capabilities. And I think at least two new gadgets have been revealed: smoke bombs which Batman can use and sneak away in the confusion, and this broadcast tracer (i think it was) to locate signals and track them.
The game also has more puzzle elements. The use of Batman's
Detective Mode which highlights things such as enemy skeletons and clues on the screen. And now this is used to perform forensic analysis at crime scenes, such as tracing the origin of a sniper round. Kinda like on the original version.
I read something about that players can now access to a criminal database that tracks the major badguys across the city that is used within Detective Mode and on some puzzles.
One thing was really a good improvement. The art director said that the Detective Mode's use will be changed alot since alot of players completed the 1st game mainly using the mode all the time. And I have to agree to that with personal experience ^^
And what comes to the Riddler Challenges...they are also be present, but they will require additional effort to locate these ,something like, through interrogation of Riddler's thugs.
There's so much new that they haven't even stated and I will defenetly get this game.
Not sure how reliable this info is but I've seen interviews and so I bet these are quite correct.