So after backing the kickstarter a couple of years ago these turned up yesterday

Website: http://www.bragi.com/

I have to say I am rather happy with them, setup takes a few hours due to firmware updating (charging them first in the charging base then plugging the charge base into a computer and dragging a download file to it).

Once setup and connected to a phone (via bluetooth) they work great.  They last about 3 hours on 1 charge however the portable base station has a battery that can recharge them 4 or 5 times.

It's a bit funny not having a cable connecting the 2 pieces together.  Will test them out on a run tonight :)