Haste may seem good at first especially for rage gen but thats where the benefit ends.
It doesn't increase dps from special attacks...only white...and doesn't reduce gcd
Although white damage is not insignificant it only represents a portion of your damage.
Haste does increase rage however which in turn allows more special attacks but Fury warriors have no problem generating rage for special attacks and will find that that extra rage is used up via Heroic Strike (rage dump). As this turns your white attack into a special you gain no rage therefore haste is all but wasted.
A far better stat to go for would be ignore armour as this increases ALL damage (including those white attacks so more rage is still gained)