EM is a massive dps boost. It gives you 20% more chance to crit for 30 seconds, and apart from this being being a huge dps increae, what it does is make clearcassting be up more, which gives you 10% more for your next two spells. ANd yea, you will find ele shammies will scale extremely well now with spell powr.

Also, elemental precision should not be dropped. 2% hit is 2% dps. For raiding the hit is more important than the instant ghostwolf which you can't even use inside most raids.