I left WoW a few weeks after the ZA/ZG release due to having to travel a lot for my job. I came back about a week ago and have noticed a big difference in the random groups I get set up with. From Cata release till the time I left it seemed like every other group I was in had someone calling names, putting people down, getting bent out of shape over nothing, or rage-quitting.
Now I go into the LFG and this rarely happens. Most groups I am in run flawlessly or the hicups along the way don't cause members of the groups to completely lose it. I've even seen members go out of their way to help newer players to that particular dungeon *gasp*. I still get the random person who wants call everyone 'baddies' or 'fail dps/tank/healer' or worse even when everyone is playing well....but it is about 1/7 of the groups I am in versus 1/2 (or more) of them.
Have you noticed the LFG getting better?
Did the recent loss of subs consist of a large portion of pseudo-elitists?
...Or are most players so overgeared for the various heroic instances that being good or bad doesn't really matter?