Finally, and at the risk of getting lynched, I'm going to join the 'no female Doctor!' camp
Of course we won't, dear Perp. Hanging is too good for you. JOKING!!!!
I think Maggie Smith would make a great doctor and since Steven Moffat has juggled with the rules significantly already (I quote my Who-obsessed daughter here, rather than speaking from my own knowledge) it seems possible the next reincarnation could be female.