Hi, it's a while ago you've asked this question, but maybe you still have something on(?) this answer.
It is very good possible to connect the sony dr-bt50 to your pc, i run vista with a bluetooth usb-stick and i have a great connection. the only thing is that i can see my usb microphone in sound configuration, but it doesn't work with the pc. (haven't checked it with my mobile phone yet, so it can be the microphone is broken ... but i guess that's not the case)