I don't think it is any surprise that the next Batman film is currently being worked on, but IESB has confirmed through a "extremely reliable source" that the film is currently in the writing stage with Christopher Nolan, Jonathan Nolan, and David Goyer. Personally I just think its common sense that these three guys would be having meetings and writing stuff down to develop a script for the next Batman film. Once again IESB talked to producer Chuck Roven regarding the matter, and once again chuck had nothing to really say on the matter.
IESB: We've been told that Jonathan, Chris and David are working on the new Batman script. Do you know the direction they’re going or do you wait for them to formulate something more complete before you get involved?
Chuck Roven: The creative driver of the project at this point is Chris. There’s really nothing more for me to say about that. When he feels that he’s got something to talk about, then we’ll be able to talk about it.
IESB: I know you can’t tell us who the villain or villains are, but do you personally know?
[Big smile and a laugh] CR: I really don’t want to talk about that project right now.
Which is code for "please leave me the hell alone." But IESB makes a point to say they double checked on the matter and they are definitely hearing the script is being written. I just assumed that it was being written.