So the surprise introduction of Jenna-Lousie Coleman as Oswin Oswald in the series premiere Asylum of the Daleks raises the question: "How does a dead Dalek girl end up being the Doctor's companion?"
Anyway--when Jenna=Louise Coleman was introduced to us as the Companion to follow the Ponds, we were told she would be introduced in the Christmas episode, and her character would be named "Clara Oswald." There is also a promise of something "Victorian."
Obviously, that was not entirely true. But how much is true and how much is misdirection, and how do we get a Companion after she's been assimilated and then blown up along with the entire planet?
So I'm going to call it here. Here's my prediction, based on almost nothing other than what I have laid out above. I have no inside information, I have no particular insight, nor do I have any record of guessing correctly about anything. Ever. At any time.
The Christmas episode will be an inversion of "The Nutcracker" (in which the protagonist is traditionally either "Clara" or "Marie.") It will be Victorian (the high tide mark for Christmas traditions) and Clara Oswald will be from the past--an ancestor of Oswin, much like Eve Myles played her Torchwood character's own great-great-grandmother in the Doctor Who episode The Unquiet Dead. My guess is that the Doctor will take the role of the Nutcracker, will take Clara to a sci-fi version of the Land of the Sugar Plum fairy, and she will come with him and he will have to NEVER tell her about her many generations removed descendant Oswald--but he will hint that he knows she is brave and smart and strong, because he has seen her DNA in the future.
Now I just have to remember to come back here at the end of the year/series and see how well I did!