I think they're trying to address the "no CC" issue that many shaman complain about, without making it a 'true' CC. It will be effective in PvE and mildly effective in PvP, since it is dispellable and will probably be subject to diminishing returns.

As for totems affecting raids, I expect that they will limit the stacking abilities of nearly every totem, particularly Totem of Wrath. Even just two elemental shaman on a raid would mean an additional 6% to spell crit and 6% to spell hit for everyone, and that's not all that minor, IMO. They may allow healing stream to continue to stack, though. I cannot imagine people bringing extra shaman to a raid to stack it. I'm interested in how they'll handle Tremor Totem, though. Being able to protect every member of a raid from fear, charm, and sleep effects with a single totem? Having that kind of power stack? I can't see it happening.