In a recent interview, Nolan described Inception as “the biggest challenge I’ve taken on to this point.” He goes on to say.
"I grew up watching James Bond films and loving those and watching spy movies with their globetrotting sensibility…. We get to do that here, not just geographically but also in time and dimensions of reality as well. We get to make a movie that’s expansive, I suppose you’d say, in four dimensions."
Nolan says that his new movie is "more personal and enormous" than anything he has done before..
“We tried to make a very large-scale film with The Dark Knight and with this one we wanted to push that even further.”
Still not saying too much about the plot. The trailer looks cool, but it could be about anything! I like that, too few movies these days have any mystery to them.
UPDATE: Sorry folks, I misread the /film article(thats what I get for not properly checking primary sources!). It was the original interviewer for the LA Times that suggested Nolan may "revisit Gotham City for his next feature"..Nolan never said it himself. This was very kindly and eloquently pointed out to me by the ever friendly and respectful Quagmire in the comments section:)
Thanks to /film for the info.