Now that I have almost a week of playtime under my belt with the warlock, I'm going to think out loud for a bit. I left the game sometime after patch 3.2 hit and before 3.3 hit. According to the "Dots and you: The Affliction Warlock Thread" thread over at Elitist Jerks (EJ), there were the following changes in 3.3:
The general playing style remained unchanged, yet the buff to pet scaling via talents as well as the new [Glyph of Quick Decay] increased the damage output significantly. As a consequence, Corruption can now be refreshed by Shadow Bolt and Drain Soul, making the rotation more forgiving especially in the sub-25% phase. Currently, Affliction seems on-par with Destruction when it comes to single target dps.

As a result, I have not had to change my rotation hardly at all since coming back, and I've been able to step right back into things. There are still a few things that have changed, however.

Where's my spirit?

The only major change that I can find documentation for is that our Life Tap spell no longer scales with Spirit. In addition, the Warlock class will not be stacking spirit after the expansion. But the spirit stat still gives spell power.

So this goes in my book as "don't worry about it". I'm not going to trade off all my spirit-based gear, but I will prefer spell power gear over spirit gear as we get closer towards the end of the year.

Talent specs

Currently, I'm still running my 53/1/17 spec, with an emphasis on the Succubus. This is only slightly different then everyone saying use "56/0/15" or "55/0/16".

The major difference between the two currently recommended spec is "Cataclysm (4% mana reduction for your destruction spells)", namely our filler spell of Shadow Bolt, and "Dark Pact" (DP) which steals mana from your pet. So it's a bit of a toss-up and take your pick depending on whether you want to use DP or not.

This all seems to be driven by the simulations showing that a Felhunter now puts out more DPS then a Succubus pet.

Succubus vs Felhunter

Unfortunately, nobody bothered to document by how much DPS difference we're talking about in exchange for a pet that I really don't like. The only thing I've seen is a quote that "my felhunter was doing 450-500 DPS", which doesn't then explain how much DPS the succubus was doing with 2/2 in Demonic Power under the Destruction tree. At a guess, I'm betting it's about a 100-150 DPS difference. Which is sizeable... except that raid DPS is usually now in the 5000-9000 range. And that means a 100-150 DPS difference is between 1% and 2%.

Plus, there are still times when I need to pull out my Imp for his health buff. So it makes sense to have those 2 points in Demonic Power, even though I'm an affliction-spec warlock.

Frankly, I'm not yet sold on the Felhunter.

My pet rules

I think my pet rules are going to be:
  1. No mage/priest and there are other ranged casters, use the Felhunter for the Spirit/Intelligence buff. Mages provide a better (or equivalent) INT buff and priests provide an equivalent Spirit buff. But if there's a 2nd warlock who is using the Felhunter, then I'll pick something else.
  2. No warriors? Get out the Imp for Blood Pact. The imp is also useful for fights where there's too much AoE damage near the boss.
  3. Do I have 2 points in Improved Felhunter? Then I might go back and pick the fel puppy.
  4. Do I have 2 points in Demonic Power instead? Then I'll use the succubus for DPS.
My pet as affliction just isn't that much of a DPS boost/loss if I pick a different one. And it's a lot of fun to get out the Doomguard or to drop an Inferno towards the end of a fight.

Some of this is also because I almost exclusively run 10-person raids, so I often need to fill in a missing buff using my demons.

Gear

Gear upgrades are coming fast and furious this first week. While I don't have any T10 pieces yet, I'm about halfway through having enough frost badges for a 90-emblem piece. I figure it will take me another week before I have enough to get a second 90-emblem piece, so maybe two weeks for a T10 set bonus.

GearScore: 4300 -> 4600 (target 5500-5900)
WoW-Heroes: 2187 -> 2482 (target 2700-3100)
Be Imba!: 530 -> 569 (target 600-700)

Most people are running around in mostly T10, with a gear score of 5500+, so I still have a long way to go. But it's a start. The target numbers are what other people are running around in.

Hit numbers, I need something between 394 and 421, depending on whether we have a draenei in the raid. We almost always do, so my target is 394 hit, with a ring or something that I can swap in for 421 hit if needed. With my current gear, I'm sitting at 425. My current cloak has 28 hit on it, so that's probably what I'll keep around to swap in/out.

Pet testing

So I did some testing of Succubus vs Felhunter. Xav's gear score is only around 4600 (2 piece T9 bonus, 2 piece T8 bonus). Here's the numbers after doing 2 million DPS to the level 80, non-raid test dummy. In the last test, I moved 2 points from Demonic Empowerment in the Destruction tree over to Improved Felhunter.

4200-4300 - 53/1/17 - the classic, pre-3.3 affliction spec, with Succubus
4150-4200 - 53/1/17 - the classic, pre-3.3 affliction spec, with Felhunter
4200-4250 - 55/1/15 - post-3.3 spec, with Felhunter

So far, I'm not impressed.