Research efforts look at the human body as a medium for tactile input “technology” (and therefor they also need it as visual output surface).
That’s a really nice approach so that one don’t have to hold e.g. a mp3 player or a smartphone. But you have to have some free skin and that wouldn’t be accepted by users in winter.
In the video you can see Chris Harrison dialing with his hand – and than? Is he holding his hand at his ears and does he have a body built in microphone? ;D