There are really only two possibilities for a dedicated cat spec: a single-target build and an AoE build. The important difference here is only in three points subtracted or added from Feral Instinct, increasing Swipe's damage for AoE.
Feral players alter these specs as necessary depending on individual circumstances. Most frequently, additions or subtractions will be made to Survival Instincts (an "Oh s^%t!" button that's useful on some fights, superfluous on others), Infected Wounds (to provide a debuff decreasing boss attack speed if a tank cannot provide it), and/or Improved Leader of the Pack (a contribution to melee/ranged survivability on fights with heavy raid damage).
7. Talent overview:
The necessary talents for a cat are all in the feral and restoration trees; balance does not have anything of interest. As with Sacco's article and our column on Restoration 101, italicized talents are considered optional or situational, and those with a strike-through should be avoided.
- Ferocity: Mandatory.
- Feral Aggression: This is a decent place to dump extra talents, but is firmly optional.
- Feral Instinct: Mandatory if you PvP as a cat, but otherwise of most use to an AoE or bear build.
- Savage Fury: Mandatory.
Thick Hide: Bears only.
- Feral Swiftness: Mandatory. The cat's speed is an enormous survivability boost in addition to being an incredible convenience. It's not a direct contribution to DPS, but I have yet to meet a feral player who willingly forgoes this talent (or isn't otherwise driven crazy by the "slow" speed of the cat on other specs).
- Survival Instincts: Mandatory if you PvP, and close to mandatory for progression PvE content. However, the use you'll get from it differs across individual players, so use your best judgment.
- Sharpened Claws: Mandatory.
- Shredding Attacks: Mandatory.
- Predatory Strikes: Mandatory.
- Primal Fury: Mandatory.
- Primal Precision: Mandatory.
Brutal Impact: PvP only.
- Feral Charge: Mandatory. The cat version is arguably less useful than the bear version (which is both an immobilization and an interrupt), but either will allow you to close the distance with an enemy or boss instantly.
Nurturing Instinct: PvP only. Natural Reaction: Bears only.
- Heart of the Wild: Mandatory.
- Survival of the Fittest: Mandatory. While more obviously useful for bears, SotF allows you to off-tank in an emergency without fear of being gibbed by a boss crit, and allows additional stat scaling.
- Leader of the Pack: Mandatory. One of the feral tree's two signature talents (the other being Mangle).
- Improved Leader of the Pack: This is my favorite talent in the entire tree if for no other reason than the sheer convenience of it, but it must be admitted that ILotP is firmly optional. It is worth having on fights with heavy raid damage (e.g. Putricide, Festergut, Blood-Queen Lana'thel) and can add up to a lot of +healing done for your melee and ranged players. Otherwise, it's just going to be a steady stream of overheal. If there's another feral in the raid with this (usually a bear), don't take it -- the effect doesn't stack.
Primal Tenacity: PvP only. Protector of the Pack: Bears only. The tooltip is slightly ambiguous here, but it only increases attack power in bear form.
- Predatory Instincts: Mandatory.
- Infected Wounds: If there isn't another player in the raid who can provide a debuff slowing the boss' attack speed, you should take this. Otherwise, it should be considered PvP only.
- King of the Jungle: Mandatory.
- Mangle: Mandatory. The lynchpin of feral DPS, even if you don't have to provide it yourself.
- Improved Mangle: Theoretically, the talent is skippable if you already have a so-called "Mangle bot" (a fellow cat assigned to Mangle duty, a bear druid, or arms warrior providing the bleed debuff), but you will find an abundance of multi-target fights in raids where no one can apply Mangle to your immediate target but your good self.
- Rend and Tear: Mandatory.
- Primal Gore: Mandatory. So good that a version of it (concerning Rake) is the 4-piece tier 10 bonus.
- Berserk: Mandatory.
- Improved Mark of the Wild: Mandatory.
Nature's Focus: Restoration only.
- Furor: This was once a 5/5 talent before Improved Mark of the Wild stopped sucking, but nowadays most players will only schlep 3 points here. Because it only affects the energy you have directly after shifting into cat, it has minimal impact on raid DPS.
- Naturalist: Mandatory.
Subtlety: Restoration only.
- Natural Shapeshifter: A lackluster talent for PvE given that you're likely to be in cat most of the time, but you'll need it to get Master Shapeshifter.
Intensity: Restoration only.
- Omen of Clarity: Mandatory. One of the more unheralded contributions to cat DPS, and a tier set version of it (two-piece tier 8) is so good that it eclipses almost everything in the game until four-piece tier 10.
- Master Shapeshifter: Mandatory.
Most druids have traditionally leveled as feral for maximum efficiency and access to manaless DPS. These days, it's a toss-up whether you'll level faster as balance or feral. It's been my experience that pre-40, balance is faster; afterwards, the addition of Improved Leader of the Pack (2/2 at level 42) and Mangle (at 50) to the cat's arsenal gives a slight advantage to feral. Honestly, you should spec your druid however you most enjoy. As long as you're not grinding in the early version of bear form or (heaven forbid) tree form, it'll go quickly.
Shifting Perspectives has a guide on how to level as a druid from 1-80 covering talent choices and rotations for cats. To gloss that advice, your usual "grinding rotation" in early levels will be to apply Rake and then Claw an enemy to death, or Claw to a 3- or 4-point finisher in the form of Rip or Ferocious Bite. In the levels before Mangle is available, a Glyph of Claw is a good investment. As soon as you get Mangle, drop Claw from your bars entirely, drop the glyph in favor of something else, and try to forget that Claw ever existed.
For heirlooms, you should actually ignore the PvE melee leather shoulders (Stained Shadowcraft Spaulders at 40 emblems of heroism or 60 champion's seals) and pick up its PvP counterpart, the Exceptional Stormshroud Shoulders (200 Stone Keeper's shards). Remember what we said earlier about agility trumping raw AP? That's why. Unfortunately, there's no agility on the melee leather chest heirloom (Stained Shadowcraft Tunic at 40 emblems or 60 seals), so you're stuck with that.
The heirloom weapon of choice is the Repurposed Lava Dredger, available for either 65 emblems of heroism or 95 champion's seals, and the only useful trinket is the Swift Hand of Justice (50 emblems or 75 seals). If you win the Kal'uak fishing derby, you can add a Dread Pirate Ring to the set.