Just tried it. It's a bad demo. It makes me think "oh man, this tech sucks". The main thing I don't like about it, is that you have to make a ton of micro movements with your neck the whole time. That's uncomfortable. I think anything that can use this head tracking in such a way that:
- requires infrequent head adjustments
- does not require calibration
- provides an extra efficiency boost over just using a touch control
...would be a win for this type of control. Honestly, I can't think of many applications for that. "Nod to confirm"? ...except that's likely less easy than tapping.
Honestly, if someone wants to do "tracking", I'd suggest body tracking instead:
1. stick the iPhone by the TV, camera visible and pointing at you
2. have it connect via HDMI or AppleTV
3. use it Kinect style, full body