got one of these yesterday for a sunday transcon.. had a CR1 waitlisted already, but since i received the email less than 100 hours before the flight, and the CR1 hadn't cleared, i wanted to take a look. alas, worthless, and i agree that the email implied the upgrade was ready for the taking if i wanted to pay..
but then the CR1 cleared overnight anyway. :-) (really thought i was going to be toast if it didn't clear at least 120 hours out, since i'm 2P now, and it's a sunday transcon.)
oh well, glad they didn't give me a chance to pay... (really, if they'd take the infamous "tens of dollars" from me after i had a CR1 waitlisted for three weeks, i would not have been happy with that... but this seems to be an overdone version of "go check your flight options and see if we're offering upgrades, if you can think to do that once you get to my itineraries"..)