People thinking that the Wii will be supported beyond the launch of the Wii 2 (or whatever it ends up being) are forgetting the past. Nintendo systems are still defined by Nintendo games, and Nintendo will drop Wii like a bad habit as soon as they release its successor.
Lets take a look at recent Nintendo system releases and the suport given by Nintendo to the preceding system after its release:
- N64 launches in 1996. Nintendo publishes 2 games for the SNES from 1997 onwards (both Japan only).
- Gamecube launches in 2001. Nintendo stops publishing games for N64 by the end of that year.
- Wii launches in 2006. Nintendo stops publishing games for the Gamcube by the end of that year.
Other than the NES, Nintendo has never really supported a home console after the release of a newer one. I don't see why things will be different this time. They will probably just do what they always do and convert any late Wii projects to Wii 2 projects when they're ready to make the generation leap.
Third parties will continue to publish a few titles for the Wii, but they will follow Nintendo's lead and divert most of their efforts elsewhere.
I think a similar pattern would have shown itself in Nintendo handhelds if Nintendo had a better idea of how insanely successful the DS would end up being. They had no problem killing the Gameboy color after two and a half years when the GBA was released, even though Pokemon was selling buckets of GBCs. However, they seemed to hedge their bets with the DS, continuing to offer full-fledged support to the GBA for all of 2005 before it was apparent that the DS was going to take off.
