Sony knew they had to start the press conference strong, and so it makes sense that they kicked off their E3 press conference with Uncharted 3 with a demo that literally turned the game on its head.
The press conference demo showed off a cruise ship level, the ship getting battered by a vicious storm, huge swells making the ship sway back and forth. Naughty Dog is clearly showing off their level design in full force this show. Drake stumbles and grabbed onto things as the huge ship rocked, the entire level completely unsteady. He moved inside the ship, under massive chandeliers, then back out, shielding himself against the rain that battered the walkways.