I play moonkin and two classes seem to be really broken.
Retribution and rogues are impossible to beat as moonkin. I cant cast anything else than instants because continuous interrupting and retri is impossible to keep far and damage is too much. Since only damage i can do is moonfire and starsurge, I cant do any real damage.
Actually any melee is impossible to beat. Balance druid needs instant roots and cc like mage to be viable dueling class.