First of all, if I remember right, the full body gesture system was an april fools joke, funny you bought it :-p (no offence)
But I think that PocketTouche can have a real potential. The video demonstrated stuff like writing but I guess that that would be ridiculous to do in public on top of that it would be real cumbersome. But it might be of good use when you want to skip a song or mute an alarm (or call), so for small gestures.
Question remains than, can it be produced cheap enough. Only then will a 'gimmick' be added to real devices