Re: The Joker - What would you do now?
I think that TDK was implying that Joker and Batman would definitely meet again and that he would always be the arch-nemesis. "You and me... I think we're destined to do this forever." If there was a really good role for the Joker to return, i would be for him being recast, since there is already a precidence of recasting with Rachel Dawes.
Holmes, though, didn't own the character to such critical acclaim that people spoke out in horror when the character was recast.
Just because it's futuristic doesn't mean it's practical.