One day a fault developed with the seatbelt sensors on the rear seats. He kept getting the warning beeps to fasten the belts when no one was on those seats.
It was still in warranty so he took it get fixed. The dealer pulled his driving logs from the on board computer/data recorder and said his driving was too aggressive and that violated the warranty.
Truth be told his driving was terrible. I accepted a lift home from him once, and only once because his driving scared the bejeesus out of me. But that being said how could that affect the pressure sensors in the rear seats?
It took some solicitors letters to get the dealer to agree to a warranty repair.
I think its inevitable that manufacturers are going to use all this data to stop you claiming under your warranty. "Oh dear you slammed your door too hard one day, I'm afraid that invalidates your warranty". Insurers will demand this data in before giving you a quote. Its also likely that there will come a time when this data will be used to help price your car if you sell it or trade it in. And of course the government will want to use positioning data to automatically issue parking fines.
And this ignores all the obvious security risks that come along with this sort of stuff, for example all those BMW keyless car thefts.