BruceS:
As my real work involves a project which uses GPS technology coupled with cellular technology along with engine diagnostic information to track a very large fleet, I would say the governor idea is quite possible. Now depending on what information the devices are set to send back it could be very invasive or more benign. But to achieve what the governor would want probably more information would needed to be sent back to determine what roads were traveled along with distance on them instead of just total miles for a period.
But to get an idea of the type of information that can be captured and sent if desired include: location, speed, direction, engine status (from as simple as engine off/on to rpms, coolant temperature, battery voltage) along with any other sensor type data. By combining things like determining if the vehicle is idling with the engine on or sitting with engine off. Or combining with GIS applications and data it can be determine things like whether a vehicle is speeding at the location and for how long the vehicle was speeding etc.
But to give
A friend of mine writes GPS cell phone software applications in Slovenia.
His "fun" web site is http://triptracker.net/
but I can't quite remember the name of the professional site, its somthing like Klika or Krika.
The app he was showing us a couple of years ago showed the path he took going through the city, with the narrower lines representing when he was on the bus, and wider lines when he was walking.
It's all so cool