I think of the 3 basic DK specs, unholy gains the least of expertise.

With the instant refund of runes on a dodged attack, the only real loss is the loss of a GCD worth of dps. Which is still a lot, but an affordable something for unholy.
Whereas blood and frost are so locked into their rotation without any real margin for error that they value expertise higher.

[edit]: For clarity sake, im not saying expertise is useless for unholy. Far from that, I'm just saying that relatively I assume we get less out of it than a blood or frost DK.

I would recommend trying to obtain high ilevel items with expertise already on them. The ring from Ulduar25 trash, or the tier 8 chest come instantly to mind. You should NEVER be gemming expertise, and its probably ill-advised to enchant it either, as Strength is still a far greater DPS stat for us (in every spec).

Regarding the lack of expertise on Ulduar gear, I'm showing [Worldcarver] being a slight upgrade over [Voldrethar, Dark Blade of Oblivion] (weapon DPS loss included) for those with the orc axe expertise racial.

Makes gearing for expertise significantly easier, not to mention readily available.

That doesn't make any sense. What are you using for this?

I want retouch a subject that we discussed earlier.

At the moment there is a lot of discussion going between Necrosis and mainly Improved Unholy Aura.
However it might be nice to revise our view on Morbidity, now that 2 weeks of ulduar passed.

Methods already confirmed that Morbidity is in fact one of the worst dps talents that we pick. I could redo the calculations but thats kind of redundant.

I was one of the people that put morbidity forward as a must have talent, because pre-3.1 we had to base most our experience on naxx.
Even though the 5% more Death Coil damage per point is really low dps (Death coil is less than 10% of your dps usually so you're talking about 0.5% per point at best), I personally valued morbidity for its 15 second reduction on the DnD cooldown, which in naxx i rated as near invalueable for overal dps performance.

HOWEVER, now that we experienced Ulduar a bit I have to say. I hardly ever use Death and Decay, and when I do, I can usually get away with 1 DnD per 30 seconds.

I'd like to get some more input on this but the way i view it is this:

---===[ Possible Spoilers up ahead ]===--- (although i think most people know ulduar by now)

Trash: Mostly useless, because a lot of the trash disallows aoe'ing for several reasons. Maybe this comes back in the future, but so far i found there is few trash that can be aoe'ed. And we often crowd control trash now, so even pestilence is out of the question.

Razorscale: One of the fights that promotes using Death and Decay.
Ignis: No AoE involved
Decontructor: No AoE involved
Kolagarn: We personally put melee dps on the boss while ranged kill the adds, so for me there is no AoE here. And even if there was 1 DnD/30 sec would more than suffice
Iron Council: Single target DPS
Auriaya: AoE involved, however 1 DnD per 30 seconds would suffice
Hodir: No AoE
Thorim: This is one of the places where extra AoE would come in handy, if you stay in the arena that is.
Freya: The wave with the exploding adds can initially be aoe'ed down a bit before starting single target (to make sure they dont all explode at once), however 1 DnD / 30 sec more than suffices for this initial aoe.
Mimiron: No AoE
General: No AoE
Yogg-Saron: No AoE (havent been in phase 3 yet, so maybe there)

However that in total brings us to 2 bosses where the 15 second reduction might be somewhat useful, (Razorscale and Thorim) And in both cases, I think the loss of the 15 second longer CD is not devastating.

In return however by switching those 3 points from Morbidity to Necrosis we get nearly 1% more dps. If you assume necrosis is 0.8% dps and morbidity (in best case) is 0.5% dps, then you gain 0.3% dps per point.

Just some food for thought, maybe others can disagree on my assessment.

This would make unholy/blood look like this:
Talent Calculator - World of Warcraft

And unholy/frost like this:
Talent Calculator - World of Warcraft

---------

Another alternative is to put 2 points in Morbidity, like earlier mentioned. To keep the benefit of the shorter cooldown and transfer the last point to necrosis for more dps.
Because in practice very often people only use DnD once per 20 seconds anyway, since that always fits better with runes. (Easier to get the rotation right).

This post in the UI forum discussing a new generic priority queue addon got me thinking. Afabar posted an unholy DK priority list to that thread here, but I found it to be incomplete and outright wrong in places. With the scourge strike glyph, I feel unholy is better suited to a priority list than a rotation. Many of my changes are debatable, which is of course the idea.

if all runes are on cooldown, runic power <=75, and Empower Rune Weapon is available, cast it
if Runic Power >=50, Heroism/Bloodlust buff is up, and Summon Gargoyle is available, cast it
if Blood Plague debuff not on the target or duration <=3s, cast Plague Strike
if Frost Fever debuff not on the target or duration <=3s, cast Icy Touch
if Scourge Strike available (F/U runes or double Death runes), cast it
if Blood Strike available (B rune only), cast it
if Bone Shield buff is gone, B runes won't refresh as Death runes (second half of standard 20s rotation) and Bone Shield is available, cast it. With Blood Tap, if it's available. (1 GCD, as blood tap doesn't generate a GCD)
if Unholy Blight buff not present and RP >= 40, cast it.
if RP >=40, Death Coil.
if all runes are on >=1.5s cooldown and B runes won't refresh as Death runes (second half of standard 20s rotation) and Blood Tap is available, Blood Tap and Ghoul Frenzy (1 GCD, as blood tap doesn't generate a GCD)
if all runes are on >1.5s cooldown and Horn of Winter is available, cast it.

For the most part you are describing instances in which you do or do not use DnD. You make the point that those talentpoints may be spent better in Necrosis. Ok, I can go along with that. However this is still based on the idea that IUP is superior to Necrosis. An idea that I think is still up in the air.

The actual challange from my point of view is to compare Morbidity with IUP, because I clearly remember people arguing the exact same way about IUP, i.e.: "IUP is bad on this, this, this and this boss"

The statement "Morbidity is in fact one of the worst dps talents that we pick" just sounds a little awkward in the face of IUP.

Even on the fights where DnD would be useful, I have found that with 0/10/61 the lack of Subversion makes DnD a risky proposition on both Thorim and Razorscale. The adds on those fights die so quickly and they have to be picked up so fast that DnD could pull aggro. In fact, I've noticed some aggro issues on trash in general with the above spec. I'm considering dumping Morbidity for Subversion. Of course, my aggro issues might not be 100% accurate, as there is a particular Rogue who loves to ToTT me at the beginning of trash pulls.

I'd add "deathcoil when approaching rp-cap closer than 30 rp" between reapplying diseases and casting SS. Also reapplying diseases when less than 3 seconds are left is to early in my oppinion. I'd cast SS until at least one disease has actually fallen off or FU won't be available for at least 3 seconds after the first disease falls off (rough number).

The discussions are completely orthogonal. Even with frost subspec, you don't have enough points for all of them. Sure, if you choose to skip IUP for more DPS, then you can get 3/3 morbidity and 5/5 necrosis with frost, but with blood subspec you still are short two points. The cookie cutter specs have, to this point, either been 1/5 necrosis with IUP or 3/5 necrosis without, and both with 3/3 morbidity. Revising them to put necrosis over morbidity is a totally reasonable point for debate, though I suspect it should remain in the unresolved column and be left to personal preference, much like IUP is. And let's be honest, in either case we're talking about, at an absolute maxiumum, a 2% swing in DPS, so if people want to take a 2% single target DPS hit for better mobility or aoe, that seems pretty reasonable to me, whether permanently or simply as an alternate spec.

Hi, new to the theorycrafting thing, but willing to learn

First of all, loving the discussion, but i do have some questions, since i suck at math. I read and learned a lot thanks to this thread. Now i'd like to contribute and show my 3.1 plans.
Do not mind the armoury for my char, as i am trying to go on a whole new direction with it. The guild wants me to dps, so i'm gonna do just that. I have chosen Unholy for that purpose. I have not yet respecced as i would like to do this one right.

I plan on the following specc: DPS Unholy tri-Build

I don't want you to question if it's the best cookiecutter spec out there, this specc just fits my playstyle. I do not like pets, thus no garg or permaghoul. I use 2h weapons with rune of the fallen crusader. Like the stuff being discussed now, i've chosen not to go with morbidity as i do not use DnD, instead opted for necrosis.

Would i be right to assume that a decent rotation would be :

IT -> PS -> SS -> BS -> BS -> Unholy blight (rune dump)
SS -> SS -> PS -> Pestilence -> Deathcoil (rune dump)

I would glyph disease to keep the diseases up without doing another IT + PS to keep max SS'ing. For the third rotation i would keep it the same as the second, but since i have more runic power each time i would be able to DC twice. Then i start all over if the mob isn't dead. I do wonder if i can keep this up with deathrunes, or if i am completely missing the ball here and need to use more bloodrunes, thus not being able to keep up the rotation.

I've tried testing it with Kahories DK simulator and with pre-raid gear (i am casual) i would be around 3400 dps.

Would all this be viable, or do you guys think never to raid with someone who uses this build ? My apologies for the horrible english, and i hope to contribute.