I have tried a jawbone icon and it was pure trash with Siri, I have since switched to a Plantronics Voyager Pro+ and it seems to work perfectly with siri, as long as you don't have the window down going 50 mph with the wind blowing directly on the mic. It also supports a2dp bluetooth profile, and you can pause the music with the volume buttons. Not the most elegant looking ear piece but six hours of talk time, and 10 days of standby make it worth it.
I have also found that when siri starts to have network problems it seems like it starts to get everything I say wrong when it does finally start working again. Not sure if it's "learning" this somehow or not. I just switch Siri on and off to reset the learning and everything seems to work flawlessly again.