One of the many goals with hunters in Cataclysm was to make haste a more attractive stat and a more intuitive stat. Back in Wrath, haste was an almost comically poor stat for hunters. Just about the only thing it did for us was increase the rate of fire of our Auto Shots. While it was still a beneficial stat, it was so much worse than all the rest that hunters would bend over backward and jump through hoops to avoid dirtying themselves with it.
Blizzard certainly succeeded in making haste a more attractive stat for us in Cataclysm. It did not, however, score well on making haste more intuitive. In fact, haste is far more complicated and less intuitive than ever before. At certain points, haste is very good for us; then when we get past those haste plateaus, suddenly haste is much, much worse, until we hit another plateau when it's suddenly good again. And of course, these plateaus are radically different for each spec.
While I'm glad we no longer have a nearly useless stat, I do hope that Blizzard continues to tinker with haste to make it work a bit more smoothly and remove some of the unnecessary complexities. In fact, I even have an idea of where to start.
Join me after the cut for Frostheim's haste design theory.