Honestly I think Moffat should go too to be honest... while his first series in charge (with Matt Smith) was great I think they've really dropped in quality with Smith's second and third series. There's the odd good episode, yeah, but it feels to me like it's only one or two of the whole series that are decent, when, in older series, for me it was completely the opposite, only one or two were naff and the rest were great.
Still though, it'll be interesting to see where they go with the next Doctor based on who they pick - personally I'm not too bothered about it being a man or a woman, black or white, it'd just be different and I reckon I'd get used to it in time. However they should go with the person best suited for the role out of all the candidates, rather than just get a "token" non white/female lead.