Why would they? They did two films moved on. ^
They would if they were asked about it. I'm suprised nobody has asked about them possibly returning for atleast one more 'cause so many fans would love that.
Nolan's vision will be over in 2012. That makes room for like a Batman Beyond film where Keaton as Bruce is the old mentor with a new younger Batman in the forefront. A cameo by Michelle Pfeiffer would be cool as their was no resolution whatsoever to their tragic relationship from Returns. This could totaly work and could give Burton/Keaton a chance to do a third version of their vision of Batman and pretend those crappy Shumacher films never happened- ala Superman Returns.

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