Elizabeth the First runs through a forest, presumably while chased by a Zygon, a Zygon roars while breaking out of a glass case or through a window, and the Tardis smashes through a wall, ripping a Dalek to pieces. Which begs the question of why the Doctor doesn't just run the Daleks over with the Tardis all the time.
This is followed by a walking shot of the three Doctors (Reservoir Doctors anyone?) and a sign of some surprising conflict with this exchange:
Tenth Doctor: Just for once, I'd like to know where I'm going. Eleventh Doctor: No, you really wouldn't!
Obviously it refers to some kind of advanced knowledge that the Eleventh Doctor has but the context remains a mystery. It looks like it takes place pretty far into the episode given the tone of those lines, and it probably refers to the Eleventh Doctor experiencing part of their encounter with the Hurt Doctor before the Tenth Doctor. My other guess would be that it's about the Tenth Doctor's regeneration but that just seems too inconsequential and after the event to get such a prominent spot in the trailer.
Another shot of the Hurt Doctor with what looks like Rose in the background (It's hard to be certain with such a shallow depth of field) as he says "I'm looking for the Doctor." And we end on the Tenth Doctor quipping "Well you've certainly come to the right place." Judging by these scenes and the comparison of the brainy specs and the Sonic Screwdrivers, my guess is that early on in the episode, all points converge on Elizabethan England. Queen Elizabeth is present during the Screwdriver comparison, we know that the Zygons are there, and the Sonic and specs scenes as well as the "You've certainly come to the right place" moment all look like they happen in the same place. And now, as promised, that oh-so-spoilery picture and my guess about just what it means...