Yeah my Mazda oem head unit has Bluetooth built in (I've heard Toyota is adding Qi charging to their new models).
I'm considering doing something similar to what this guy did with the wireless charger. I'm going to wait until I already take my car apart to add an amp and sub though.
ps: doesn't need to be a lumia, my 8x does the same! (tho I admit I would prefer a Lumia lol)