Cool ideas, but I say no way any time soon. That TD-30 you mentioned is very light for a 3D video camera. The only other alternative for lighter 3D is the HD Hero 3D system, but as you probably know, that does not give much versatility during recording. You could do a lot with adjustments in post, but you can't even zoom in with the Go Pro cameras. And some say the Hero2 is still squirrelly in 3D, so you might even be better off with the first HD Heros.
What do you want so light for? I took 3D video from a flying octocopter with the HD Hero system.