How do you do a fighting game on the 3DS? You do it the Super Street Fighter IV way or this Dead or Alive way. Pretty similar. Touchscreen is optional but helpful for those who are fighting-game-challenged (like me).
Note that Dead or Alive Dimensions, a "launch window" game for the Nintendo 3DS, will also answer many of the unanswered questions in the Dead or Alive series. That's what the press guy from the game's publisher Tecmo told me. He seemed dead serious, so I guess there really are unanswered questions?
What I can't show you in this video is how good the 3D depth effect was in Dimensions. With the system's 3D slider turned up, the top-screen combat appeared as if taking place in a roomy, deep environment extending inches beyond the system screen. It was surprisingly cool and some of the better (and subtler) 3D I've seen on the 3DS system.
The game's Metroid: Other M fighting arena wasn't shown in the version of the game I saw. So you'll have to look elsewhere to see it.
(Additional video production work for this post by Bryan Ridgell.)