Just like, well, most other Apple keynotes Epic revealed a new game in the Infinity Blade Saga. Details are remarkably vague, but we do know it's a dungeon crawler-y sort of game and it's "coming soon." If I were a betting man, I'd say that "soon" is going to be either on or before the launch of the third-gen iPad on the 16th.
Check out the trailer:
Infinity Blade: Dungeons Upcoming AppWatch Button Watch App