Yes, that is The Doctor riding a horse. It seems the seventh season of "Doctor Who" will take Amy, Rory, and The Doctor to the old west.
A student at Cardiff University noticed a "Doctor Who" episode being filmed outside the physics department. He was able to get this video of the shoot.
And yes, it does contain a date. September 1, both BBC and BBC America will air the first episode of the new season of Doctor Who. Is it September yet? How about now? Now?
A very short teaser clip from the first episode of Doctor Who's seventh season.