I use the Jabra Stone bluetooth headset when riding my Vulcan. It's slim profile makes the fit inside a helmet no problem and the helmet actually helps keep the headset in my ear so I can hear (without the helmet the fit of the jabra is so lame on my ear that it almost falls off).
In practice, a fully charged headset can last me anywhere from 10 minutes to about 1.5 hours before I lose the bluetooth connection. This requires getting the helmet off to reset the stone in order to get it working again, which you know is a major pain because once I get on the road pulling over to stop after just 10 minutes and adjust my headset is the last thing I want to do.
Actually having a phone conversation with it is definitely possible, but extremely difficult around 20-30 mph and near impossible at higher speeds. Maybe adding foam will help with reducing wind noise, but stock application makes phone calls while riding a virtual non-option.
I thought the Stone would be a perfect solution, but it has several flaws. The bluetooth connection drops easily, especially if there is physical interference. The controls are "cool" but don't always work well, which doesn't matter if you wear a full face helmet anyway since you can't reach them. The main advantage is that it plays media (music, gps nav, etc) in addition to phone audio. To my knowledge, most bluetooth headsets only support phone audio, so a unit like the Stone is still a huge improvement over other bluetooth options.
I also have a skull candy set of wired ear buds that block out the sound great, but don't do so well with some sounds, like song voals and synthesized speech (gps nav voice).
I'm always looking for an improved situation, but these are the options I use now. I'd be interested in hearing of any setup people have found to work well.