Elemental shamans' DPS should at least be on the same level as moonkin, given moonkins have more armor and usually more hp as well. So I am not too worry about shaman's DPS as they are buffing us. I am sensing the trend (design choice by blizzard) is to not stack any classes. Blizzard is obviously spreading things out on all classes. and I expect that to be continued. This is great for solo, more choices, really fatal for us boxers, pvp wise at least. With that said, I wouldn't be surprised to see diminishing effects on same spells hitting the targets (wild guess on my part), another level of challenge for coordination and call for diversity.