The Elemental shaman guide on this forum says the following:
Howevver, does anyone actually used this? And on which fights? As far as i am concerned, the fights with intense burn phases are of a dps check during the whole encounter which should make EB the superior choice.For Elemental Unleashed Fury is right out. It's damage contribution is lower than the other two talents, and it complicates the stationary rotation while removing options for the mobile rotation. Of the remaining two, Elemental Blast is ahead of Primal Elementalist by 2-3% in an ideal test, however it does complicate the rotation a bit whereas Primal Elementalist is easier to use and works better on encounters with burn phases.
In short, it will come down to personal preference between Elemental Blast & Primal Elementalist.
WTB your opnions on this