To those saying 'just keep Capaldi', you all know he'll be going one day. I do think it's a bit inappropriate for the media to start speculating on 'the next doctor' just on the basis that they are assuming he is leaving after series 10, when actually it may not be the case at all, but at the same time, there will actually be a time, be it sooner or later, when he leaves.
Shouldn't really need pointing out to people on here that it's part of the nature of the show.
Also, on the subject of Aidan Turner, never watched Poldark and have no intention of doing so, seeing that he seems to only be popular in that on the basis of the fact he takes his top off, but I have a lot of respect for his acting skills from his time on being human. Doesn't exactly feel a natural fit for the doctor though. A bit to 'macho' I think.