Warrior - Threat, Gems, etc.
I never played my Wartank as my main but as of late have decided to raid with friends again and they need it.. So having said that:
The second spec (Prot/arms) is the one I'm using for boss tanking.
So what I'm asking is: Everything. My gems, enchants, everything. I want to know what I'm doing wrong, why its wrong, and how I can do it better.
My general boss rotation is:
SS -> Rev -> Dev -> Conc Blow -> TC
Though I am having trouble with threat.
Thanks in advance
You should not use Concussion Blow for threat. Not only does it not generate a lot, but stunning enemies means they won't hit you, giving you less rage. Shockwave is the exception simply because it draws so much aggro in an AoE. Your rotation on mobs should go charge, shield slam, Thunder Clap (once all the mobs are in range), Shockwave, then spam Cleave, Devastate, and Revenge, using Thunder Clap and Shockwave whenever they're ready. Switch targets periodically if you find yourself having trouble with aggro, but ideally, people should be focusing your target. If they're not, try skulling your first target before each pull.
For bosses (or other single targets), your rotation is simpler. Charge, Shield Slam, Devastate, Devastate, Devastate, Shield Slam, etc. If Shield Slam refreshes due to Sword and Board, use that instead of a Devastate. You'll also want to throw in a Thunder Clap here or there. Slowing down boss attack speed by 20% is a great mitigation tool. Use Heroic Strike whenever you have more than 40 rage. Interrupt or reflect spells when possible. Revenge does a bit more damage than Devastate, but it seems to be worse for threat, so don't use it unless you have a nice threat lead.
I recommend trading out Glyph of Blocking for Glyph of Shockwave. Warriors don't have great AoE tanking, so you should glyph to cover that up. Glyph of Resonating Power isn't all that great, either, unless you're having MAJOR rage problems.
I'm assuming your first spec is the one you usually use for tanking. Get rid of Cruelty, Improved Cleave, and Unbridled Wrath. I'd also recommend losing Improved Revenge. It's not all that important in my experience. Instead, go into the Arms tree for Deflection, Improved Charge, Iron Will (or Improved Heroic Strike), and most importantly, Impale and Deep Wounds. Those last two abilities will give you a significant damage (and threat) boost (bear in mind that Incite makes Cleave and Thunder Clap crit a lot).
You'll generally want to gem for stamina, regardless of socket bonus. If the socket bonus is stamina, though, it can be worthwhile to put in a hybrid stamina/dodge gem if that matches.
In general, block value is pretty worthless in the endgame (part of the reason I recommend ditching Glyph of Blocking), so I would trade out Titanium Plating on your shield for the 20 defense enchant. I'm too lazy to go through the rest of your enchants right now, but stamina/hp, armor, defense, and dodge are your best bet.