For an amusing video discussing it check out
What is the Best Hunter Pet?
The language is kinda bad but it is funny.
(Brief explanation, it took Blizzard over a year to make the spore bat even cast its ability. The poor bats just haven't ever lived that down.)
Sadly this post isn't going to help the 'must have one pet crowd', unless your looking to change. Their like the Shaman I met who only cast [Frost Shock]. Didn't matter if [Earth Shock] did more damage in short fights and that with [Flame Shock] more in long fights - he just wanted to 'Frost shoooock!'
Actually the Shaman comparison is a good one with their flexible buffs, more on that later in grouping.
So Ill take a look at the 'best' pet for soloing and grouping.
For soloing you need a pet to keep Agro (hold the Mob's attention while you shoot it) and doesn't die. Depending on how you play you end up with about 6 options. The links are to stock builds.
1) A Tenacity (Tank) pet with a defensive build. This pet takes everything the group of enemies give them and slurps it down with a side of bacon ready for more.
Best for hunters who want a tank that doesn't die (easily) and can handle a pull of big groups of enemies.
2) A Tenacity pet with DPS taents to help rip off faces of a group while keeping the targets attention.
Good for picking up adds and helping to kill your foes, a good balance. Its good to note that the extra damage means extra threat.
3) A single target Tenacity built Hunter Tough(TM).
Like the first it has hard core survivability, the lack of an AoE pet debuff is made up for in having a rock solid damage reduction cooldown for emergencies.
4) A Single Target Tenacity Pet built for damage or a Cunning pet with tanking talents.
The Cunning only has a minorly annoying AoE so you can pull agro off an add easier but it does a bit higher dps than the tenacity with only slightly worse survivability. The tenacity trades defenses for damage with the benefit being higher threat.
5) A Ferocity pet with tanking talents or a Cunning pet set up to play distraction.
At this point your pet is holding agro as much off the damage its doing as its actual tanking abilities. Be wary of exceeding its threat and seeing a mob in your face.
6) A ferocity pet talented to claw/claw/bite.
Now all of those were set up with a Marksman or Survival Hunter in mind, but I'm pretty sure the Beastmasters can figure out how to toss their extra points in.
So, that gives you a general idea of what pet builds and pet families work in those roles. So those are the best right? Well..maybie.
/I/ think that the best ferocity pet buff is the cat's [
Next Ill look at picking the best pet in a group or even raid. Because that pet you chose can be the difference between a successful boss down and a run back from the graveyard.
Have fun huntering and remember; Just because you cant see them stalking you ...
doesn't mean they aren't there.