Heck, if Bruce Wayne were a timelord, it could give a (bad) explanation of why he's played by different actors in all the films. As Adham said in FYEO #1 (SHILL!), James Bond has been thought of by some as a timelord just because the entire series gives little regard to casting continuity as a whole.
On topic though, if there ever was a Batman/Dr Who cross-over, expectations would be very, very high indeed.