Sting: 64 to 86 Nature damage, decreases target's armor by 1260 for 20 seconds (level 80). While affected, the target cannot stealth or turn invisible.
The damage from Sting is actually a little bit less than the focus dump Smack, but it also costs only 20 focus, where Smack costs 25. This leads me to believe that a Wasp is not even losing a tiny bit of damage with this special on auto-cast, but the Wasp probably does not gain any damage either.
The affect of Sting besides the damage is the real reason to get a Wasp. Lowering your targets armor by 1260 is amazing vs. anyone with low armor. Also the affect of not allowing stealth or invisibility is a big counter to a Rogues and Mages (great counter to instant invis from Arcane Mages).
Being a Ferocity pet, Wasps end up with the best tree for a BM hunter. They can easily crit in PvP and can be instantly rezzed with Heart of the Phoenix.
Overall I love my Wasp for PvP and PvE. The only thing I would change about it is the annoying sound of its wings buzzing... and now you can get rid of that noise by doing the following:
You basically just need to make a blank file (I just made an empty text file and renamed it accordingly) called "SilithidWingLoop2.wav" and put it here in your Wow game folder:
*wow program path* \Data\Sound\Creature\SilithidWasp\SilithidWingLoop2.wav"
That will override the default buzzing sound with nothing at all, which is blessed compared to what they do now. All their other sounds will play normally.
It seems all wasps at the moment use this same sound resource.