The difference, to me atleast, is I see the DS as a quick pick up and play thing, or something to do inbetween classes outside.
I like my consoles to be an expierence. The HDtv, the 5.1 sounds...yes graphics don't mean everything, but they play a large role.
I agree with you, but I don't think graphics are essential to creating an experience.
Shadow of the Colossus, even compared to many PS2 games, looked (and more to my annoyance, ran) like crap, but heavens if that wasn't an enthralling expierence. Where as many games with bump maping out the wazoo just kinda fall flat. The original PS1 Resident Evil is another good example of a medicore-to-poor graphical effort, but still creating an environment completly fitting to the game's intent and experience.
I think the experience factor rests somewhat in the hands of the power of the system, but the lion's share of the responsibility is the game developers': how well they know the system and how much time and effort they put into it. In that regard, that the Wii isn't much different than the Cube, may give the Wii an inital head start on creating immersive games. Coupled with the remote, I think we're in for a lot of treats if developers give a rip.
How it will hold up in the 5 years originally proposed remains to be seen, but I'm more than slightly optimistic.