I continued to use it though and I learned its strengths over time; it makes a GREAT sniping tool. If you have a target highlighted when you cast it, it is guaranteed to hit that target.
I know that doesn't seem too useful as things currently are, but I have to wonder how good this ability will be in Inferno. It can already be somewhat annoying to damage specific targets if they like hiding or running away (the little goblin dude and skeleton Summoners come to mind), but I was using haunt to literally guarantee their death on sight. How useful will this be when enemies start using CC on us or maybe we will encounter more foes with even more annoying battle tactics.
I want to build my Witch Doctor entirely around Haunt and Locusts. The overall strategy looks like it is going to be DoT->CC->Run->DoT->CC->Run. I wonder how useful this is going to be. Recalling my previous Diablo 2 experience, the ability to run around while damaging foes was a golden strategy.
What does the forums think? How about builds; I want to use Haunt and Locusts, but what other abilities might be useful to synergize with this? Slow and steady wins the race, as they say.