Several interviews have Nolan saying that he's actually working towards an end to the Batman story instead of the regular feeding an unending amount of sequels like most movie/comic franchises.
whomod said: I generally don't like it when people decide to play by the rules against people who don't play by the rules. It tends to put you immediately at a disadvantage and IMO is a sign of true weakness. This is true both in politics and on the internet."