I've been thinking about two Doctor Who issues that have come up in recent days - the regeneration limit and state of fandom.
The first is the regeneration 'limit.' I truly don't understand how anyone who is a fan of the show and has thought about the show for more a few minutes could seriously think that the BBC will end Doctor Who when the thirteenth Doctor leaves. I mean, really, why would they do that? So long as the show is still successful there is no reason honor a plot point that is a couple of decades old, and even if by the time Thirteen rolls around it isn't successful which means they decide to end production, there's nothing saying that they couldn't resume the show at some point in the future. (They do have track record for such behavior...I'm just saying.) Have I missed the memo where this a documentary and the BBC will have no choice but to stop filming since the Doctor is no more? Not to mention that we have another time lord character who is well past his twelfth regeneration who does provide a nice already made canon loophole so the writers don't even have to do any work to come up for a reason why the Doctor can make it to Fourteen.
The second is the thought that once David Tennant leaves, fandom will go back to some golden age that it was before. Some pre-fangirl golden age when Who fandom was a much intelligent and refined place to be (by which I assume they mean that people weren't having ship wars or talking about the hotness of the Doctor, but instead having grudge fights over the interpretation of obscure plot points y/y?). I hate to break to anyone who is longing for those days again when fangirls were in a distinct minority, but that's not going to happen. I think I count as a Ten fangirl under any definition that you would care to use, but I know I'm not going anywhere. A certain percentage of viewers who are Ten/David Tennant fans only will probably leave, joining those who are unhappy about Moffat as showrunner. However the rest of the Ten-only fans will stay and either become fans of Eleven or hang around and bitch about how much Eleven doesn't match up to Ten, thereby joining all the other fans of previous Doctors who don't like the other Doctors (please note that I'm not talking about all or even most fans of previous Doctors, only those who stick around and become bitter because the new Doctor isn't their favorite). Eleven himself will attract a new cadre of his own dedicated fangirls who will squee, write fanfic, and spend great amounts of time dissecting his performance and viewing all of his previous work. Fangirls are not going to go away. If they annoy you, the best you can do is try to avoid them.