Just a small answer to the guy asking which classes we can kill as shaman...
I'm usually spec enh : I kill retadins with equal gear to mine. But it's true that when a retadin got all its CDs it's a really tough enemy (not as tough as a Subt. rogue with all its cds ^^).
And the easiest classes (not means they are easy to kill, just easiest) to kill : priest and warlocks.