I came across three interesting “Snowmen” costume variants over the course of my research.
"Doctor Sherlock"
The first, I call the “Doctor Sherlock” variant; even though it came and went rather quickly in the actual special, apparently somebody deemed it important enough to somebody to merit at least two publicity photos!
For this particular variant, Eleven appears to have simply swapped out his “Snowmen” frock coat and donned an appropriately-styled hat for a more traditional Sherlock Holmes look.
The remainder of the costume ensemble (shirt, tie, waistcoat, trousers) appears to be the same.
Flipped Shot
The second variant (which I also mentioned in my velvet waistcoat analysis) appears to be the result of a shot flipped during post-production.
Observe how the waistcoat buttons in the reverse direction:
Behind-the-scenes
And third, there’s this peculiar “variant” from a behind-the-scenes interview with Matt Smith and Jenna-Louise Coleman, during which Smith appears to be both in make-up and costume for the middle portion of “The Time of the Doctor” … except for his boots!
Instead, he was sporting a pair of blue, white, and red sneakers!