Ever since i first saw the talent listed/leaked from wotlk, I've been wondering:
If you use multiple Thunderstorm's at the same time (i.e. multiboxing without castsequence), will the knockback effect stack?
I doubt it will, but if it did it would be interesting if they'd fly 4-5 times as far XD

But in general, they have indeed added an entire knockback system, and you will see knockbacks happen in several places.