The report began at Batman-on-Film about an anime "Batman." There is a memo about at PG-13 anthology project presenting short stories to fill in the time between "Batman Begins" and "The Dark Knight." Comic Book writer Brian Azzarello and writers David Goyer and Josh Olsen are attached to pen some of the stories.
Batman-On-Film also has behind the scene pictures, the link shows the Joker preparing for a scene.
As talks continue about Batman it seems Jonah Nolan may have begun work on the script to follow up after "The Dark Knight."