Hi-Fun's gloves are Bluetooth "hand sets" with the speaker built into the thumb and the mic in the pinky. You then use the "call me" sign language to perform a call.
Pairing and call end buttons are on the top of your wrist. Seems that the only concern is the max volume on the thumb speaker and possibly the quality of the mic in loud settings. At least you could say "Sorry my thumb can't hear you" or "I cannot hear you through my thumb".
Hi-Call should be out in the beginning of October 2012, just in time for the cold weather.
$4 OFF $40 Sitewide Coupon with code: MB4OFF Valid from: 2012.8.1-2012.8.31