That's actually very common in most of the trucking industry today.
All semi's are built with a "black box" installed from the factory. These computers record speed, RPM's, engine temp, idle time, braking, oil pressure, exhaust temp, RPM's when you shift gears, MPG's, and just about everything else you could imagine. It also records the time and date of EVERYTHING.
As far as the computers with GPS capabilities go, a vast majority of the trucking companies have been using these for quite a few years now. Not only can they track many of the things I listed above, but they can also track your location, how long you've been at that location, and all kinds of other great stuff. Qualcomm's OmniTRACS system is the most used system at this time. '85 or '86 is when they started putting these sytems in semi's.