In the last four days, I have leveled a toon from 77 to 80 and two to 81.
I like it and I don't...I know MoP is gonna be a bitch at the start and that's not even counting heroics.
I recall a friend tanking hero Deadmines...he said something like this "Trash are like bosses and bosses are like raid bosses". I guess his pug had wiped five times even before the first boss.
I am playing heavily on my daughter's account, trying to get a few more toons to 85 for the Theramore scenario. It's money in the bank if we can run it a few times...once we figure the damn thing out!