Sarah Michelle Gellar and Charisma Carpenter have no chance. Joss has already said he doesn't want anyone from his time on Buffy.
Mischa Barton is also in the running (God help us), as are Eva Longoria, Monica Belluci, Taylor Cole, Evangeline Lilly, and Catherine Bell. So it's all pretty much in the air at the moment.
Lucy Lawless sounds like a good name that I haven't heard thrown around, she could definintely carry off the balance between power and femininity.
