I could see this coming at some point with the new headset for the PC that reads thoughts and emotions. At only about £100 right now (not forgetting production costs will be down significantly by the time Nintendo's next console comes out) it's a no-brainer.
What scares me is the pace of technology here, thought control has been a dream of man forever, and now it's becoming commercial. Next we'll see thought-controlled appliances. Scary, huh?
And head-tracking, motion control and thought control can only mean one thing: virtual reality simulation is only just round the corner people. With almost life-like graphics arriving next generation (I can only assume after the leaps and bounds the PS3 made over the previous generation's graphics), video games are gonna start dominating.
If I may use a cheesy phrase...
The future's now!
EDIT:
Just read all the negative comments. Nintendo aren't going to make totally thought-controlled games. Games could artistically use differing moods and emotions (thought-control means emotion-control btw people) to change colours and backgrounds in the game, which could be cool. Otherwise, thought-control could be used in conjunction with an ordinary game to emulate psychic powers, or perhaps to activate more subtle things like the focus in Red Steel. Thinking "focus" to activate the power would work much better than pushing the Wiimote forward quickly.
Think of the thought-control as more a complementary feature than a new control system. And if Nintendo make it Bluetooth-connected again (which they should imo, PC connectivity has probably significantly boosted Wiimote sales), it could be for PC use. Instead of a remote control for your media player, just think "play" or "menu".
See the possibilities people?
Thought you would.