I dropped my paladin tank, and moonkin and replaced them with a DK and shaman. So I'm at 4x shaman and a DK tank. The healing stream totems and magma totems are just too good. And with Ebon Plague that the DK brings, I don't need the moonkin for the 13% increased spell damage.

Also, the DK doesn't have to wait on mana like my pally tank did, and the DK brings 15% increased run speed to the party. The DK also holds aggro REALLY well, just as good as a pally tank.

I lost blessing of wisdom and a pally aura though, as well as gift of the wild and moonkin aura. I rarely used innervate and thorns.

So maybe it's break even, but it's just a lot simpler to play 2 classes vs. 3. I also think shaman do much better AOE now with magma totem and of course chain lightning. AOE wasn't really an option with the moonkin since I'd have to manually target.