No way they'll do a woman... I just don't see it.
Why? In 50 years they've never had a woman, so they shouldn't have one now? There's something in regeneration that prohibits a sex change? If that was the case how come in all the incarnations that I've seen (Tennant and Smith), one of the first things they do is look in the mirror and be glad they were in human form and not something else? Maybe I just don't know how Regeneration works, but if you're changing into another body or form, it shouldn't be conducive to one kind, should it?