Paid Ford their money and got the usb in a few days, via USPS. It came with the usb drive and a clear set of instructions, which are pretty basic: start car, put usb stick in receptacle, and don't turn the car off until you're done, "which should be about 60 minutes." Ninety minutes later, it finally finished -- I'd driven random freeways, checked out Alviso, drove some more...still updating...drove some more...stopped and got a chili dog at Mark's (easy to eat outside the car and let it run under my watchful gaze.) Now it's about an hour-and-fifteen, but it's doing what it's supposed to (updating, restarting, repeat) so...then finally about 90 minutes later, the "complete" screen came up.
I can't tell any difference. But I got to drive around in the car I enjoy so much...that's a win.