Historically, Nintendo's home consoles have followed a cycle of an innovative console followed by a Super-version with better graphics and a more ergonomic controller (NES -> SNES; N64 -> GCN). I could see them doing that with the Wii -- making a console that's basically what the PS3 is right now -- and I could definitely see them calling the next console something with Wii in the name. Brand recognition is important -- both Wii and DS are more powerful names than just Nintendo right now. The Game Boy brand lasted fifteen years; I could definitely see the DS and possibly Wii brands lasting that long too (DS is already halfway there if you assume the 3DS will last at least three years). Timing is the big question. It's odd that even though it'll've been four years this November, and the Wii was already outdated (on paper; not in principle or practice) when it came out, it doesn't really feel like it's time for a new console now. Still, I'm half-expecting some kind of incremental upgrade to be announced by E3 2011. Probably not this year, so as not to steal thunder from the 3DS, but it's possible.
One weird pattern I look at is comparing the history of Nintendo's consoles to their controllers. The comparison first struck me when thinking of the original description of the DS as a "third pillar" and comparing it to the awkward N64 controller. The DS was the middle prong of the N64 controller. It was something very new and different. It was presented as being an addition to the two pillars/prongs we already had (home console and portable console, buttons and d-pad), but the reality was that there were never supposed to be three. You only have two thumbs. The DS was meant to replace the Game Boy just as the analog stick was supposed to replace the d-pad. The whole three thing was just a PR thing to give them options if it failed -- if developers didn't like the DS, they could go back to the GBA; if developers didn't like the stick, they could go back to the pad. I then carry the analogy on. The Gamecube controller is the Wii and the DS. The analog stick caught on, so it's now the primary one, with a vestigal d-pad stuck onto it like the GBA port on the DS. The buttons on the right side are simpler than the N64's, although all the ones you need are still there, and there's also another stick over there, which could maybe represent the motion-sensing of the Wii. So then I try to carry the analogy out further, with the Nunchuk and Wiimote representing, respectively, the DSi/3DS and the next console. But I don't really know what conclusions to draw from the comparison at that point. The d-pad, which was representing the Game Boy, has been removed from the DS side and put onto the console side -- does that mean anything? And what does the two of them being physically separate from each other signify? I don't know. Interesting comparisons to make, though.
