Christopher Nolan recently spoke about Superman and Batman in an interview. On his approach to Superman Nolan said, “A lot of people have approached Superman in a lot of different ways. I only know the way that has worked for us that’s what I know how to do.” Describing writer David Goyer’s vision of Superman Nolan said, “He basically told me, ‘I have this thought about how you would approach Superman. I immediately got it, loved it and thought: That is a way of approaching the story I’ve never seen before that makes it incredibly exciting. I wanted to get Emma (Nolan’s co-producing wife) and I involved in shepherding the project right away and getting it to the studio and getting it going in an exciting way.”
Describing his third Batman film Nolan said, “Without getting into specifics, the key thing that makes the third film an great possibility for us is that we want to finish our story, and in viewing it as the finishing of a story rather than infinitely blowing up the balloon and expanding the story. We have a great ensemble, that’s one of the attractions of doing another film, since we’ve been having a great time for years.” This indicates that this will be Nolan’s final Batman film and will close the current franchise.
When asked if Batman and Superman will ever crossover Nolan commented, “Each serves to the internal logic of the story. They have nothing to do with each other.”