The thing that annoys me more than anything is when they address me in a loud voice by name and ask me (as a Gold) if everything is to my satisfaction with a deeply insincere look on their face. That and the smug announcements which no other airline seem to have. And the charity thing at the end that was embezzled by a crew member (it's something we're very proud of here at BA ...).
I'm very close to moving to SQ! The only thing stopping me is that they don't have premium economy.