They were playing Resident Evil games on the Nintendo 3DS in Tokyo this past weekend. Were you not there? Neither was I. But we've video of the games being played. They look mighty good.
This is Resident Evil: Mercenaries 3D, which is based on the survival mode from Resident Evil 5 (pardon a couple of the pauses, the live-stream choked a few times).
And there is more Mercenaries 3D right here.
Finally, here's the trailer for Mercenaries 3D