As a BM Hunter you will want more Attack Power than Agility, but I prefer to keep as much Agility as possible to keep my crit% high enough to be worth something for Go for the Throat. I wouldn't worry too much about since in outlands almost every piece of equipment you get will have an attack power bonus on it. Pre- Outlands expect your AP to be 450-750 depending on your agility and AP bonuses already, but post BC even once you hit 63-64 your AP will be more around 850-950 at LEAST without even trying, using just quest rewards and random drops.
My peronal preference for stats go like this, and I'm a lvl 65 BM Hunter myself and I don't PvP much.
1)AP
2)Agility
3)Crit rating
4)Intellect
5)Stamina
Strength is not even an option for Hunters as it gives us no bonuses whatsoever for what we do, and it also does not affect your pet, so Strenght = no.
Stamina and Intellect may switch places depending on how much you PvP, but I solo a LOT and hate downtime, so the longer I can go without resting the better, plus at 64 you get Aspect of the Viper, which gives back 25% of your intellect every 5 seconds so the higher your Intellect the better.
PvP is a totally different animal than PvE, that said your stat priorities will center around AP and Stamina, period, with Agility being a close third and crit rating being equal to or higher than agility depending on you build.
The reasons for this are:
1)You can't kill anything if your dead, so the longer you can survive the better which is why Stamina is #1 on ever class priority list of stats
2)In PvP steady DPS is non-existant since you will be moving so much, so burst damage reigns supreme so high AP outweighs your need for agility as you want every shot to be as damaging as possible.
PvE = stand still point shoot and worry about your shot rotation and your mana, normally.
PvP = run around trapping kiting and jump shotting while getting the occasional drop on someone and dumping all your mana into the first 3-4 shots, Aimed(if you have it) Arcane, Multi, Steady (when you get it)and Serpent Sting (I like it for the small bit of extra damage, but be sure you don't have to trap after this otherwise you just look stupid for trapping and then your DoT letting him go). You dump all your mana because there is no sense trying to conserve mana in a fight for you life and you're gonna die soon anyway and get rezzed with full health and mana, so dump it all go die and have fun.