I've had the chance to try them a few months ago, and my only concern with them (while cool), was that they would suffer the same fate as either: bluetooth hand

I've had the chance to try them a few months ago, and my only concern with them (while cool), was that they would suffer the same fate as either: bluetooth hands-free kits (aka douchebagy), or segway (aka dorky). The only killer app I think is driving directions, that was nice.