SimulationCraft, a tool Mograin, Rivendare, Gorefiend and Thassarian would have used
 

This whole post is a quote from zimeron:
Please note that we do not have a release out yet with 4.0.1 mechanics. If you would like to use the tool you have two options until we push a release.
-Download and install from the SVN (Note: to build the GUI you will need QT installed on your system.)
-Use a compiled version of the command line available for download from here (I upload these as time/need allows.)

The full source code for the Cata branch of SimC can be found at: simulationcraft - Project Hosting on Google Code
The 401/Cata DK module itself: sc_death_knight.cpp - simulationcraft - Project Hosting on Google Code

Full wiki output for 4.0.1 can be found at: DK401 - simulationcraft - Project Hosting on Google Code



Scale Factors:
Full Text Output:

When looking at the wiki, please take it with a grain of salt. We are actively working on the modules and as bugs are found, it can quickly become outdated. As I finished generating the last wiki output, a change was put in lowering the damage of the army/ghoul/gargoyle to better match live numbers, so while all profiles will decrease, unholy will be decrease more compared to the frost profiles. You can find the revision number the wiki was based off at the top of the file.

If you are unfamiliar with the command line of SimC you can find many examples at: Examples.simc - simulationcraft - Project Hosting on Google Code. An important reminder is that the program is currently for level 85 characters by default, so when using SimC with your level 80 characters, please include the following in your .simc file.
If you encounter any bugs or have any feedback, either leave it in this thread or open a ticket (preferred) at Issues - simulationcraft - Project Hosting on Google Code.

Did a quick sim with my Frost DK, it looks like only white hits are implemented at the moment?

e: Furthermore, it looks like it's giving me a stat weighting for Int, which should probably not be happening.

What's your action list?
DK is differen from all other classes because the "ready? hit it!"-style does not work, so you have to tell the sim to setup sequences.
I have no clue how many things from the frosttree are in. :/

What do you mean when you say action list? I imagine that's a parameter I'm supposed to be setting pre-sim, but perusing through the options in the software I can't find anything to change.

The Unholy module is indeed the furthest along. It should be accurate for most PVE raiding talents and glyphs in the Unholy tree and basic talents in the other two trees. Gargoyle and Ghoul damage are not yet correctly implemented. I did an audit of Unholy a few weeks back and brought it mostly into correct numbers against 3.2.2. When compared to my DK in a raid, numbers were very close (and exact on target dummies when nothing is proc'ing). Unholy is my primary spec which is why I focused on that first, but much of the work (ensuring baseline abilities and procs are working) is shared among trees, so I don't think the other trees will prove quite as much work, hopefully.

For a Ret or Hunter, it means the Sim hits that button in some predefined order when the ability is ready. That doesn't work well for DKs due to diseases and death runes. Frost would be tricky with UA and Rime usage (maybe ignore UA).

The DK module does not come with default-actions yet, if you don't tell him what he should do, he will pretty much only auto attack and nothing else

action lists a pretty straight forward

Take flask, eat food, go into blood presence, get that ghoul out, start auto attacking.
The tricky part with DK is that you don't hit things that are ready, because most of the time multiple skills are ready, you want to hit them in a specific order!
This WON'T! work for dk
With this setup SimulationCraft will do:
PS > PS > IT > IT > BS > BS
SC sees PS and has UUFFBB ready, so it performs a PS.
After that GCD it crawls the action list again and sees the PS, now UFFBB ready, so it sees no reason to not perform the PS!
Same with IT, BS
It will not perform any SS with such a setup

That's where "Sequences" come into play, a sequence gets run through action by action:
action1 > action2 > action3 > action4 ...
When it reaches the end, the sequence is flagged as 'done' and will be skipped, you have to tell the sime to restart a specific sequence so it will get used again

To start a sequence:
If name is not supplied it will be called 'default'
To restart the sequence
For the name, the same applies as for sequence setup
So a rotation for an 3.2.0 unholy-dk would probably look like this: (just the main rotation without special cooldowns)
The dk will now do the following

1. Go through the sequence:
   PS>IT>BS>BS>SS
   
2. Now the sequence is done and therefor skipped when the action list is searched for 'the next action that is ready'
   This will be Death Coil in this case, which will be cast as often as we have enough RP
   
3. The sequence is done and we don't have enough RP for another DC, so tell SimulationCraft that our 'default'-sequence is now ready to start again.

Correct me if I'm wrong, but won't that listed Unholy Sequence recast diseases before they are about to expire? I can't quite tell, but from what I can decipher it looks like as soon as you run out of RP you'll recast diseases and BS even if you have Death Runes and whatnot. Furthermore, such a system won't work for frost, since half of what I do is reactive (KM/Rime, etc).

Yes it does, but that's the 3.2 unholy rotation you know. :7

Regarding KM/Rime: Just tell me what options you need in which actions and I'll add them.

Didn't know that actually.

Regarding KM/Rime, there needs to be some sort of priority system set up. KM should be dumped on the next available global, even if diseases are about to drop. KM should use Rime if it has procced, and Frost Strike if it has not. Rime needs to be held until KM procs, even if that means letting it expire naturally. I wouldn't think that this would be too hard to do with a few conditional statements, but my c++ skills are still in infancy and I haven't taken a serious look at the code for this yet.

The current UH rotation casts PS and IT on 10 second intervals, so about 5 seconds before the dots expire.

edited for being tired and lazy.

Anyone a clue how HB scales with AP?
Ah, found it in the Think Tank DK:PVE, is it still 10%?

It's actually 0.2 now, they changed it way back in 3.1.

Ok, changed it to 0.2.

Was there any testing done with 3.3 SS? Didn't find anything in the unholy thread.
Things that effect the Shadow damage
x1.04 2h Spec
x1.00 + 0.15 + 0.05 + 0.2 + 0.1: Blood Presence, Desolation, Bone Shield and Black Ice are additive to one another
x1.02 Bone Shield
x1.13 EP Debuff

Things that don't effect it
x1.10 Rage of Rivendare

I hate you blizzard :x

Updated OP with newest additions

DRW and Rune of Razorice are the only things missing I think

RoRI seems to take 2% of weapon damage, without AP scaling?
Scales with BP,BI,BS,2hspec,EP but not Tundra Stalker?
Procs on everything except BB/DC (procs for HB/IT if in melee range)
Is there a PPM known for RoRI?