I have been reading the replies from your initial post and they all are interesting.  One would think it is about time these equipment manufactures would have some utility running on board the tractor to "gather" data much like a quick shop or other type of merchant does to start looking for interesting facts about the "business".  Just like they may discover they sell more glazed donuts during morning coffee and say perhaps chips with pop in the latter part of the day..............farmers could then query the tractor data set to find interesting correlations that have been talked about here.  Things like draft, speed, fuel flow, yaw, pitch, roll, gear, rpm, etc., etc., could all be queried with a capable GIS and the associated lat, long, locations on earth to find profit opportunities by cutting costs and/or increasing profits through the queried results.

The merchant quick shop analogy above was put into my head years ago, which I believe is still valid today, by Todd Peterson...ex UNL professor....now in the Pioneer world.

 A Christmas wish list that most likely won't happen this year.

 Arnie