Well, look no further than this article from Coming Soon:
Empire magazine talked to Christopher Nolan , whose new film Inception opens July 16, and got some great quotes from the helmer on the next Batman movie, coming July 20, 2012, and next Superman movie, targeted for a holiday 2012 release.
It was recently revealed that he would take on a mentor (or "godfather") role for the Superman movie, but he's not that comfortable with that title. "It's much more specific than that," he explained, "What it is, while David Goyer and myself were putting together the story for another Batman film a few years ago - you know, thrashing out where we might move on from 'The Dark Knight' - we got stuck. We were just sitting there idly chatting and he said, ' By the way, I think I know how you approach Superman,' and he told me his take on it. I thought it was really tremendous. It was the first time I had been able to conceive of how you would address Superman in a modern context. I thought it was a very exciting idea."
Nolan said he took that idea and pitched it to Warner Bros ., and the studio got excited, too. "But it's not something for me to direct," he added. "It's something we were just trying to put together a vision for, and then find the right person to take it forward."
What's important to Nolan is finding the core of what makes the character so indelible; he favors the back-to-basics approach. "What you have to remember with both Batman and Superman," he told the magazine, "is that what makes those the best superhero characters there are, the most beloved after all this time, is the essence of who those characters were when they were created and when they were first developed. And you can't ever move too far from that."
He still hasn't officially signed on to direct new Batman movie. "No I haven't. There is a point where you're just being precious about it and people get annoyed, but the God's honest truth is I work on one movie at a time. I'm only capable of doing that, so my head will continue to be firmly in ['Inception'] for another few months."
There are some things, though, that Nolan can confirm. "My brother is working on the screenplay. We came up with a story that we are very excited about. We particularly like where we are taking the characters and what the ending is... There are things for me to be very excited about in addressing the characters again. But ultimately it always comes down to the script, and can we make a great film from this? That's something I will firmly be turning my attention to figuring out fairly soon." It will be, he said, "the finishing of a story rather than infinitely blowing up the balloon and expanding the story."
Empire asked whether the villain could be a returning (and recast) Joker. "No," said Nolan resisting to elaborate, "I just don't feel comfortable about it."
Nolan reiterated that you won't be seeing a Batman/Superman crossover in his movies. "Marvel are doing what they do and people will respond to that really well, or they won't," said Nolan. "It's not something I ever really applied a blanket rule to, but Marvel characters are very different to DC characters, and the key DC characters are very different to the minor DC characters. You've got to go back to that element of, 'What do I see when I close my eyes and think of Batman? What do I see when I close my eyes and think of Superman?' And for me a big part of that is their individuality. They are extraordinary beings in an ordinary world. And the reason I think the two are fascinating is because Superman is very specifically superpowered and obviously otherworldly; Batman is very human and flawed. They're two very different characters, but there's an elemental feeling of power in the iconography of those characters. To me that's originally because they stood alone. I need to hang on to that in my imagining of them."
-Very interesting quotes there...thoughts?