The LA Times once again has the scoop here, and Mr. Nolan told the paper that he wants this third film to “carry on with that look and feel” of The Dark Knight, specifically with respect to the “large canvas and operatic sweep” of his Batman blockbuster. That’s one of the core reasons that the film will shoot and be presented in flat IMAX format rather than 3D. Another issue is the fact that 3D presents a more dim image than a traditional projection.
But that’s not even the good bit. The good bit comes in his expansion of that comment:
There’s an intimacy at times [with spatial illusion of the 3D effect] and we want didn’t want to lose scale… our ambitions for the third movie is to complete a story that has begun. This is not starting over, this not rebooting… We’re looking to do something technologically that’s never been done before… Our ambitions are to make a great movie.