I know it's not what you're looking at, but I've just ordered the new
brodit iphone 3G car cradle with pass through dock connector.
I'm planning on mounting this in the car and using an ipod dock extender cable (available on ebay) hidden behind the facia and running to a kensinton LiquidAUX in my armrest compartment (where I have a 12v socket and an aux input).
it's not integrated with the car like you might be looking for, but it'll mean I can choose songs on the iphone itself (which I prefer), I can initiate phonecalls from it and it's nice and visible, while still getting power, outputting audio and hopefully, looking professional.
I'm hoping to get the cradle in the next few days, still need to order the dock extention cable and then I need to work out to take apart the fasia so I can neatly run the cables. Of course the telephonic connection to the car will also be via bluetooth (once I get the idrive/BT frmware updated)
I'll take some pics when it's done.
dave