Revealing mistake: At the end when the Doctor makes it snow, in the wide shot you can see the snow blows in from the left side, showing that they used a snow machine just off-camera. (00:54:30)
Revealing mistake: When the Doctor goes to toss the trio of Christmas balls up, the two times after the first toss are re-used shots of the first toss. His movements of his right arm to bring up the controller are too exact to be coincidence. (00:50:15)
Visible crew/equipment: During the warehouse battle, around when the Doctor tells Donna, "Hold on, I'm coming", the film crew can be seen reflected in a door at the right of screen. (00:28:20)
The Day of the Doctor - S7-E16
Clara: Doctor, what's going on?
Eleventh Doctor: It's a... Uh... Timey wimey... Thing.
The Doctor: "Timey" what? "Timey wimey"?
Tenth Doctor: I... I have no idea where he picks that stuff up.
Trivia: In "Human Nature", when John Smith (The Doctor's human identity) is talking about his parents, he says their names are Sydney and Verity. Sydney Newman was the creator of Doctor Who and Verity Lambert was the first producer. (00:30:00)
Chosen answer: No, no information is avalible for the identity of the entity.
Repo_Man
Season 2: The Well.
jakew25