"Bait and switch" is a pretty inappropriate term. I've yet to be baited by UA about their 1K upgrades - the UAL web site does not even mention either the N.A. confirmed one way upgrades or the systemwide upgrades.

http://www.ual.com/site/primary/0,10017,1170,00.html

Similarly I fail to see how bait and switch could be used for CO going to auto upgrades. After all, the passengers that CO upgraded automatically could very well have phoned in for their upgrades. Simply by automating some process does not make it a bait and switch tactic by the airline.