Check out footage from Ocarina of Time 3D, Steel Diver, Super Mario Land, Lego Star Wars III, and many more.
http://www.nintendoworldreport.com/video/24804
Unlike E3, Nintendo was perfectly fine with people recording footage directly off the 3DS (as long as the display was set to 2D). Here is a compilation of in-game footage from almost every 3DS game at the NYC preview event. Many of the videos include direct feed audio.
Games in the video include:
The Legend of Zelda: Ocarina of Time 3D
Super Mario Land (Virtual Console - Game Boy)
Lego Star Wars III: The Clone Wars
AR Game with dragon
Steel Diver
Pilotwings Resort
Dead or Alive: Dimensions
Resident Evil: The Mercenaries 3D
Asphalt 3D
Nintendogs + Cats
Super Street Fighter IV 3D
Kid Icarus: Uprising
Ridge Racer 3D
Combat of Giants: Dinosaurs 3D
The Legend of Zelda: Link’s Awakening DX (Virtual Console - Game Boy Color)
Nintendo 3DS system menu
Neal also makes an appearance at the end of the video to say hello and goodbye.
More gameplay videos and a multitude of interviews are on the way.
I couldn't help but notice on the Steel Diver part (1:20 - 1:33)Don't forget that the system also includes accelerometers and gyroscopes.
it looked the periscope mode was being controlled by the outer cameras on the 3DS.