Druids and Priests are the unjustified crybabies of WoW. It's hardly surprising.
To be fair, Druids cat form is indeed pretty broken. In fact, barring its utility functions theres not much of a reason to ever use it. But it's being focused on, so I'm sure good changes are on the way.
From that arguement, I also agree with Dispel. But this isn't a Druid specific arguement, Dispel in the context of PvP on the whole needs to be lessened a few notches, poor Warlock.
Priests, well, they're just idiots. Priest is on top of the game in overall utility. Great solo, amazing PvP, insane grouping. They have solid varitey and are pretty damn fun to play to boot.
As for being a Healbot in groups (this is honestly a common complaint), helpful hint!: Don't roll a fucking Priest if you don't want to heal.
Hunter probably have the hardest time finding groups out of any class in the game. People seem to think that they suck and won't invite them. I spent the most of my time (60 Hunter now) soloing quests for exp. Everyone looks at them as a solo class. I see people yelling in general at the Hunters LFG to "go solo because it's what you're supposed to do" way more often than I would like.
Huzzah! BST logic. BST was a fucking monster in a party in FFXI, it was probably overpowered, but no one would ever invite one because it was "the solo job".