In the UK I expect telematics to be widely adopted by the insurance industry. These telematic devices produce several "events" per second so 1 million events per user per day is a realistic figure as is 64Mb of data per user per day.

For the most part the data will be junk. I drive for about 3 hours a day so 21 hours worth of data will be useless other than to tell that my car stood still at a particular location.

I'm not sure how many vehicles there are active on the roads in the UK but the DVLA say that 28 million were registered last year.

If it becomes mandatory to have a telematics device in the vehicle that's about 1.8Pb of data that will have to be processed of which less than 0.3Pb will need to be retained. Not really that big in the grand scheme of things.