I would say the Wiimote, and online content such as Demos, and digitally distributed indie games.
The big argument (by Nintendo fans, mostly) is that development is atrocious this gen on the "big HD systems". Thing is, I don't see games like Super Stardust HD, or Penny Arcade Adventures costing more money than what Lost Winds is on WiiWare.
We've seen closing in on 75-odd developers on XBLA, and the majority of them are no-name indie developers - Ninja Bee, Wankano, Zen, Load Inc, MetaNet, Void Star - Some of those development groups have fewer employees than mid-tier companies in the 80's. Yet their games have made them millions of dollars.
So again, WiiMote is very very important (Nintendo wouldn't be on top if it wasnt for that), but I think, going forward, digitally distributed VC and new titles are going to be the hidden thing that we're going to look back, and remember parts of the generation for.
Back from the dead, I'm afraid.
