I attended the final seminar yesterday, It was pretty monumental too. Lasted about 3 hours (usually about half that!).
I *strongly* do not believe there will be a visor. Most certainly not infact. It's just not happening in this gen. Maybe Nintendo have a secret plan to release it in a couple of years? But from what Nintendo expect developers to produce does not seem like something that would use a VR helmet.
We got to see a few Nintendo games too, 2 from HAL and 1 from Nintendo themselves. Silicon Knights are seemingly throwing tantrums. They are not going for smaller games at all. There is a belief though for game studios to work on lots of little games and bundle them together on a single disc. A new 'Home Arcade' way of playing. They will be a lot cheaper than the big games too. Don't know if I can say this but the Twilight Princess seems to be a route of gaming they want to stay down. Not kiddy, not adult. This must be the new angle they are after; non-demographic gaming.
We also got specs! I'm not a spec sort of guy but going off the reactions of the guys there it was something special. And going off that I don't believe in a cheap price tag. Not with the things this machine is capable of. Which also leads me to believe HD will be possible, they were cloudy on the issue. Its good they announced it this late though; its a common technique used in design. Get an idea of what you want regardless of what tools you have to work with which takes out restrictions. These speeds have a very high ceiling for developers.