Like others have said, it depends on your personal flavor. Since you were saying you were having AOE threat issues, Armsman might not be a bad choice for you for that extra little edge. If you're comfortable with your threat generation, stamina might be a better option.

As for your spec changes, look good for the most part, I still am against Mark of Blood and 3/3 Scent, but again, personal choice. As far as Spell Deflection goes, so far it works well for me, but I'm primarily doing heroics and 10-mans. It has situational use as well, but for me, I think it works well. I've had it trigger off most heroic bosses who cast direct damage and frontal arc type spells (Argent Confessor, Eck, Lavanthor, Cyanigosa, Prince Keleseth, Dalronn, every single frigging mob in Old Kingdom, etc. etc. etc.) but also of some 10 man bosses as well. So far, any direct damage frontal arc spell (like dragon breaths) that I have tanked has triggered it, which makes keeping me up much easier for my healers. I'm curious if it works on the new Northrend Beasts encounter (the jormungar spit is frontal arc).

And that works for me - it allows me to tank any heroic, even more pain in the ass ones like Old Kingdom, with relative ease.

Anyways, the build you have now looks more solid, especially with Morbidity 3/3 - DnD has a nice threat multiplier which will be better than any amount of BB spam, and should help you keep your AOE threat.

Reclaimed Thunderstrike. That's only the 10 man version. If there's a 25 man version like there is with Vis'kag, then expect it to be the best in slot until you see something with multiple sockets and much much higher base stamina and agility.

But you have to wait for Onyxia to be revamped to get that beauty.

It's not exactly an argument, it's a mathematically proven fact of the matter. I suggest you spend a little more time trolling all the DR, EH, TTL, etc parts around here or at the tank spot where Satrina has done tonns of math around this subject.

Before resorting to personally attacking me, can you give some thought to the above question? I repeat, if stamina being the best stat is the only argument needed to support that all collections of gear should be gemmed only with stamina, then why is stamina-based collections not the only ones in existence in the first place? It is the best stat after all, it's going to be used exclusively after all - according to the consensus you're presenting, why not take it in gear in the first place?

Firstly, i am not personally attacking you in any way, there is nothing at all in there that would imply a personal attack against you in any way.
More importantly, with regards to the topic - the most important words are DR and MAXIMIZING the benefits of a socket to a tank.
If you are not looking to MAXIMIZE the benefits of a socket, by all means, you can gem with anything at all.

This appears to be a 'stamina is the best stat' argument in different wording. As I said, I accept the notion that stamina is the best stat. What I don't understand is that if you are going to gem stamina in all sockets without exception - generous bonuses excluded - why not pick a stamina-based set of gear to begin with? I remind that I specifically replied to a message stating that there are different sets of gear available such as avoidance gear but that they would still be gemmed with stamina anyway. I know very well the consensus of gamers; what I don't see is the reasoning behind it: Surely, if stamina is the be all and end all stat when it gets to gemming, why not be in gearing too? You do touch the subject of 'gearing is different from gemming' but I don't see the reasoning reaching that result. We have some stat variance in gear surely, but wouldn't that variance still be biased towards stamina in a 'gem stamina only' frame of thought?

The reason you would socket avoidance sets with stamina? Avoid death due damage spikes. As for threat sets, you usually have more than enough threat stats with gear only.

Why not do it the other way around? I think it's an opportunity cost issue. Gearing usually boils down to avoidance versus threat, since most pieces have generous amounts of stamina. What you're doing with gemming usually has a bigger impact in your resulting HPs. So, for example, when choosing between "gearing avoidance and gemming stamina" or "gearing stamina and gemming avoidance" you're choosing whether to sacrifice a little threat or a lot of stamina for avoidance.

If it has an ICD, it's much lower than 20 seconds. I have yet to see it failing to refresh during a boss fight.

It looks like 100% uptime (after this first proc) under typical circumstances. 20s duration with a cooldown under 10s (I've heard ~5) and, as noted, an ~80% proc chance.

You're mistaking gearing for Stamina with gemming for Stamina. Tank items of the same level have pretty similar stamina, and if Stamina was the ONLY thing to gear for then you'd be in PvP gear no questions asked. The point is that a gem slot, for a DK tank, provides a tremendous health increase, compared to relatively small avoidance benefits from the same slot. DK tanking has effective health stat weighting that is not quite as dramatic as the Strength for DPS DKs, which is to the extent that some use tank weapons when DWing as well as only gemming for Strength. But gemming for Stamina, which becomes heavily enhanced by raid buffs, as opposed to under/around a single % of dodge, parry, or even less of both if you choose defense past the cap in the same slot simply provides more benefit. Every piece of gear in the game is intentionally itemized at sub-perfect, because otherwise all gear of the same level and type looks identical. When given a specific choice to augment an item through enchantments or gems, however, the empirical formula becomes king for maximizing benefit since in that case you CAN 'ideally itemize.' So unlike DK Endgame DPS, where Strength is essentially the undisputed master of all it surveys but has to put up with co-existence, DK Endgame Tanking faces Stamina: First Among Equals.

You guys keep arguing back and forth about which type of gem has more value, and that stamina is always better than any other...but if that were truly the case, no one would go for socket bonuses, or meta requirements. The pure and simple fact is, pure stamina gems are ideal unless it is outweighed by a socket bonus which provides both avoidance and stamina, or a socket match which fulfills your meta requirement (resulting in more stamina/avoidance).

Beyond that, it looks like you're all arguing in favor of the same point, from different angles, and massively misunderstanding each others points as counterpoints to your own...