Wow this is really an useful thing.. think to people who can’t talk, they could be heard by anyone with the voice of their choice..
For now i think it can only be done inside a room, or outside but you have to wear a back-pack to move around the computer, but who knows maybe in the future thanks to the miniaturization a small cell phone will do the job (and a hat for the videocamera), actually u only need a strong cpu and a big energy-battery so having a portable kinetict should be already factible today.

After reading this, i thought to an old movie Congo.. where a professor used a wearable device to talk with his gorilla (to which he had teached the sign language), the device was made for humans who couldn t talk with their voice.. back then it looked like science fiction..