I just put in 2 new Pioneer DEH-6200BT decks in my car and truck. Unfortunately the deck does not recognize BT audio only BT phone. However it does have both USB and Aux inputs. The USB input really does do much better than the Aux even with a direct dock connection. In truth I even went back to my headphone jack since my iphone 4G is not compatible with my direct dock connection. I would like to have the option to have a bluetooth connection but I don't want it enough to change out my head unit and multiple wired/wireless remotes.
I am curious if this would work well enough to keep me happy:
http://www.miccus.com/products/blubridge-mini-jack-rx
Unfortunately my iphone causes so much rf distortion on my system anyway, I usually just put it in airplane mode.