Just a few quick thoughts.
It seems people are having very different experiences with game performance after the 1.2.1 patch. Prior to today's emergency maintenance, for myself and the guildies I'd talked to the game had been running much better. Yet I did see in alliance, region and on various blogs and forums, a fair few people saying it's running worse for them.
And then today since the emergency maintenance, it would seem to have dragged performance down a bit for everyone. Not sure what the deal is here. Most perturbatory indeed.