Yeah I really don't think this is going to happen. I think it's just wishful thinking on Alcon Entertainment. I'm hoping Nolan does his Howard Hughes pic after TDKR actually. I am interested in seeing that.
This man now has the power to do whatever he wants and he's stated before he doesn't think in terms of sequels. I think Batman will probably be it for a while in terms of sequels. Nolan is also a huge fan of the original Blade Runner. I don't think he feels need to revisit that.
I prefer he do original work as well from here on out after TDKR.
I have always thought that a Blade Runner reimagining was in order but not necessarily best served by a director like Nolan, not because he wouldn't do something pretty awesome with it.
I've always felt that Blade Runner should be entrusted to someone deeply entrenched in Japanese Cyberpunk faire. For example someone like Mamoru Oshii of "Ghost in the Shell" fame and readapt the idea to a kind of futuristic Neo-Tokyo sort of context. It would become even more alienating and hostile to a person like Deckard. And I think drawing on an Anime visual and narrative sensibility would just bring an added dimension to BR.
I'll cop some stick for this but I think Colin Farrell would made an awesome Deckard.