What is the best raiding talent spec for Warlock?

DS/SnF (0/21/40) - *Nuke Spec / Destruction*
Pros: High damage, very versatile, biggest numbers.

Cons: No instant Corruption. No Improved Life Tap; mana inefficient. VERY dependant on you not being on imp duty. If your guild forces you to have an imp out, don't use this build.

Gear: As much +damage/+shadow as possible. +crit and +hit are also important, as usual.

Weapons of Choice: You can either go Immolate + Incinerate, or straight up Shadow Bolt spam. Shadow Bolt is higher damage because it receives a larger +damage bonus (86% compared to 71% for Incinerate), but Incinerate is about 20% more mana efficient which is important in this build due to the lack of Improved Life Tap.

Summary: If nuking is your style, this build is for you. In fact, this build is a direct replacement for the 7/21/21+2 (DS/Ruin) warlocks of the pre-Burning Crusade era. DS/SnF draws its immense direct damage power from nuke-enhancing talents such as Shadow and Flame, Backlash, Emberstorm, Ruin, and Demonic Sacrifice (Succubus/Imp). One obvious drawback is that you cannot have a pet out - and in cases where it's necessary to be on imp duty for an encounter, you gimp your damage done by 15%. Two other big things you'll have to live without are instant Corruptions and Improved Life Tap, both staples of the original DS/Ruin build.

With this build, your main tools are Incinerate (boosted by regular Immolates) and/or Shadow Bolt. Incinerate benefits 15% less from your +damage gear, but is 20% more mana efficient. A few of your talents are at odds with each other. For example, SB doesn't benefit from Emberstorm, and Incinerate doesn't benefit from Improved Shadow Bolt. Your best bet is to use your brain and use one or the other (or both) based on the situation at hand.

You can also have Curse of Agony up at all times to enhance your dps, but chances are you'll be stuck on CoS/CoE/CoR duty since it's better raid dps for your affliction locks to have all of their DoTs up.

This build is also one of the most versatile; you can sacrifice different pets depending on the situation. If you're going to be AOEing, sacrifice the imp for +15% fire damage. On long boss fights where your raid can't support your Life Taps, sacrifice a voidwalker for health regen.

UA/DR (43/0/18) - *DoT Spec / Affliction*

• Pros: High damage, can have imp out, very mana efficient, awesome for multiple targets, will be helping out your raid with 5/5 Shadow Embrace.
  
  Cons: Can't think of any at the moment.
  
  Gear: As much +damage/+shadow as possible. +hit is important up to a certain point (check the Gear section for more info), but less so than other specs since you have 5/5 Suppression. +crit is even less important since DoTs cannot crit.
  
  Weapons of Choice: Corruption, Curse of Agony, Siphon Life, Unstable Affliction, Drain Life, and Shadow Bolt.
  
  Summary: For all of the warlocks out there, your time has come! Affliction is now a genuinely viable raid spec with some amazing damage over time power, especially since the debuff limit for mobs is 40 so you can rest assured your debuffs won't be wiped off by that hunter's stupid Serpent Sting. CoA, Corruption, Siphon Life, and UA are staples of this build, and with 12 total affliction "effects" on your target (from all warlocks in your raid), you can then proceed to drain life for 60% more effectiveness. Keep in mind that Shadow Embrace counts as an affliction effect. Therefore, if there's more than one affliction lock in your raid/guild, only one of you should spec 5/5 Shadow Embrace, and the others should put only 1 point into it and the 4 remaining points somewhere else.
  
  People have been debating about the dps viability of Drain Life with this build versus Shadow Bolt spamming after putting up the DoTs. It looks like SB is still the king, although Drain Life will definitely pack a punch. The nice thing about this build is that you still have Bane, so you won't feel gimped in the SB department. Also, I feel that it's necessary to note that UA does indeed contribute more to your dps than Ruin would, so you can rest easy knowing your 41st point was well spent.
  
  The biggest pro of this build is that you will have incredible mana regen capabilities with all of the leeching skills (Drain Life, Siphon Life) and Dark Pact. This build is the polar opposite of DS/SnF as far as mana efficiency goes.
  
  
  
  
• DT/Ruin (0/40/21) - *Demonology*