Well I Think it could be both depending on how the games are developed for it. It's going to be hard and theres going to be a lot of failure. People loved the wii but the thing is, it has so many kiddie games but you can't really make a all time best game with just body movements. I mean try making mortal kombat on that. Isn't going to work, your going to be stuck with mediocre games like the one they demo'd
My issue with it is, microsoft isn't and has never been innovators, they just push things to a new level. They got into the console market with video games and pushed hardware, and personally, I find it to be when the downfall of games that required a bit of thought (rainbow six, splinter cell, ghost recon, deus ex, baldur's gate, FEAR 2 etc)
Innovation has been nintendo's thing since the NES (power glove, the running pad thing, the robot...that did fuck all, light gun) zelda was the first game to save games on the cartridge, I believe the gameboy was the first real handheld that wasn't that stupid 5 pixel sprite LCD shit.
Snes brought the superscope that....didn't go very well. They had some mario paint thing where you used an snes mouse to draw whatever, the introduced internet to the system with that Satellaview crap.
then I don't think they really didn't anything innovative till the Wii
Everyone else really just pushed gfx and hardware, sony (nintendo was actually partnered with sony to create the playstation but some disagreement broke out)microsoft, sega all just pushed hardware.
so all in all, no one has hit anywhere close to what nintendo has brought to us.