I managed to get myself into Vault of Archavon (10 & 25 man) and Hyjal Summit (25 man) PUGs last night and did surprisingly well.
In Hyjal Summit, the other tank's gear score was 200 higher than mine, but I still managed to pull bosses off of him without even using any of my taunts. I also managed to be the last one standing in a couple of the boss fights, taking down Azgalor by myself with the help of only one healer who also died before the boss. Even though we couldn't finish, I still feel quite accomplished.
Afterwards, I queued for a random heroic instance and got stuck in Oculus which is one of my least favourite and one of the hardest for me to keep aggro in because of how some of the caster mobs are spread out. The DPS must have been minding their own threat because I had very little trouble with aggro, and only struggled when the healer accidentally got too close to some trash mobs before I was ready.
It was a really good night. Wintergrasp was even good and bearable when we finally lost the fortress. But I can probably expect to have a string of horrifically bad runs tonight. That is usually how it goes for me and it sucks because tonight is the night that really matters. It's one of the few nights that my guild actually raids and we are doing ICC 10.