well counter my counter argument to prove your argument. remember i never said furor is bad. i am talking about pvp in bgs. you think i never tried 3furor before? 100% that i can beat other druids with 3furor if i have 1furor and 2predatory strikes. its just more utility if you to use those instant spells rather than having guaranteed background energy recovery that can be dictated by how you play. (i think i mentioned this before)
Furor gives you enough energy for an inmediate Mangle, Rake or Ferocious Bite as soon as you shift back into cat form. Without it, you have to wait.
Not only that, Furor gives you enough energy for an EXTRA Mangle or Rake after shifting back and landing that first one. Without it, you have much less burst dps.
Furor allows you to shift out of cat form at any time, depending on your immediate needs, with no penalty.
Predatory Strikes is very situational because it requires you to build up 5 combo points and land a finishing move before you can use it. Trying to stay in and get those last two combo points when you really need to be shifting out RIGHT NOW will get you killed in pvp more often than not.
Druids already have healing and dps spells that are instant-cast already without the need for a Predatory Strikes proc. This means the key qualitative differences for the PS proc would be Roots and Rebirth. Roots might be nice, but ferals already have a huge built-in mobility advantage. Where PS really shines is with Cyclone, which we do not have at level 20.
The Predatory Strikes buff can be dispelled, whereas the benefits of Furor are always available.
Don't get me wrong, Predatory Strikes is a nice talent, but not one to be taken over Furor for pvp. But that's just my opinion, admittedly, developed from my past experiences with feral pvp against all types of classes and specs (not just hunters & rogues) and often in 1v2 or even 1v3 situations. I would not presume to write an "Official" feral pvp guide, though.