First female Doctor
I'd actually like to see this. It'd be cool to see how he reacts to his new gender and whether it changes any aspects of his personality as a result.
Billie Piper - No. Too much storyline associated with the character.
Olivia Coleman - While she was great in Peep Show and Hot Fuzz, she doesn't really strike me as "Doctor" material.
Helen Mirren (?sp) - Now we're getting somewhere.
Alex Kingston - An ideal candidate....but too much storyline already associated with her.
I think it'd need to be a more mature actress, someone age 40 or older. A 20 or 30 something wouldn't really have the air of authority the Doctor needs.