I was #1 on the upgrade list 10 minutes before departure (travelling alone), after the plane was fully boarded. And, yet, the gate agent went back and invited someone else to go upfront, and the woman brought her carryon bag with her. I sent a question via twitter and after the first standard response "the upgrade list is constantly changing", the Twitter agent told me she checked the flight manifest and the woman had booked the seat with a guest upgrade, and "was probably just hanging around before takeoff with her friend". I doubt that story because 1) then a gate agent wouldn't be sent on board to invite her up and 2) why was her carryon baggage stored in coach? I agree upgrades are broken.