I think you are right, I have just connected a spare iPhone with a broken glass and will leave that in the car. It all seems to work ok and saves the hassle of unplugging etc.Hmmm.....I don't think you can do both via that route.
I know they do a charging cradle for the 3/3g that fits in the
centre armrest. Not sure if there is one for the 4 or not
But my understanding is that you can't use your iPhone, charge,
and use it like an ipod all at the same time.
If that's right..then I'm still planning to use an ipod to the
mmi. Keeping the phone seperate for now.