I've run raids quite a few times now while staring at dps meters, and i can say shamans are good but not overpowerd. Yes, as enh i do usually beat rogues for damage, but that is only because i've been with some nooby-ish rogues, and because i'm experienced. Its all about playing your class properly.

I just like bein emh shamman because any melee dps absolutely love your buffs, especially WF.  :D