I'm not going to get into the debate of should they or should they not, it's obvious from reading the many pages of this thread that people feel strongly both ways for their own reasons. I booked, I hoped they would honor it, I filed a DOT complaint b/c I'd like to see them rule on something like this since they are the governing body...but I'm not going to jump in and start yelling about suing UA and bashing them on their twitter account...at least not yet...but I just got this in my email...and well, UA...you are just one big antagonist!:

Santiago is wondering where you are –return to united.com to book our guaranteed lowest fare, and start traveling. If there's something you still need to iron out, use FareLockSM to hold your fare and complete your purchase later.

One of my flights was LHR-SCL via EWR and IAH.

Of course, they have a nice picture of a boarding pass with my name on it, and it says 10A on it, and, as you can imagine, 10A is BusinessFirst from LHR-EWR on one of my flights.

UA, I do have some things to iron out...the ticket you canceled!! But you don't have to flaunt it in my face. That's just hitting below the belt.