New poster for the Doctor Who Christmas special!

The BBC has released a new poster for the upcoming Christmas special for Doctor Who! The episode will be titled "The Time of the Doctor" and will be actor Matt Smith's last episode as the Doctor. The poster comes with the tagline "A change is going to come..." and fans know that this means they will be getting a new Doctor. However, some recent interview with show runner Steven Moffat have suggested that more than just the Doctor could be changing in this episode. He has hinted that a part of the Doctor Who mythology could change. Could this have to do with the Doctor's regenerations or is it something that fans won't see coming?
*Click to enlarge picture.

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