I think that if this is mentioned on BOF, it IS news - it is arguably something above and beyond the rumours that have been going round since TDK was released. That's not to say that he definitely won't make the next movie, but it's not definite that he will either.
I hope that it is simply a matter of Nolan not multi-tasking, currently refusing to contemplate the Bat and giving Inception his all until it's done and dusted, then devoting all his attention to Mr Wayne's alter ego.
There has never been a great superhero threquel, IMHO. And more often than not, the disappointing second sequel has been down to replacement of a director - Donner with Lester, Burton with Schumacher, Singer with Ratner. Raimi is the exepction (though arguably having Venom foisted on him by the studio and Arad was similar, as it showed a deviation from the original vision). I can understand it if Nolan feels he can't top TDK and doesn't want to make the Godfather Part III of superhero movies. But I really hope he's up for a challenge and opts to return to Gotham city.
