If I counted right from memory, the farm I work for part-time now has 13; the biggest is also their newest - a Case/IH Steiger 535 with BIG duals on all four corners... That sumbish is YUGE...
I've noticed a lot more farmers here going tracks instead of wheels (driving by on the bike, not scientific)
I, on a personal level, hate quad track designs.
The non articulated track tractors are good. I hate the quad design though.
Did mention that before?