Is it just me, or did DKs get the bigger piece of the cake when it comes to mitigation?
Lets compare the 4 main static mitigation abilities that all tanks get. (All these abilities are assumed to be talented)
Warriors: Shield Wall - 40% mitigation 2m cd (or 60% mitigation for 4m cd if glyphed)
Druids: Survival Instincts - 60% mitigation 5m cd (couldn't find any talents to reduce its cd, 5m seems pretty high)
Paladins: Guardian of the Ancient Kings - 60% mitigation 2m cd
DK: Icebound Fortitude - 60% mitigation and immunity to stuns 2m cd
All of these lasts 12s.
Looks like Druids are the losers in this round, 5m cooldown is a bit too long. I looked around for any talents or glyphs that would decrease that cooldown but couldn't find any. Warrior are also behind the other tanks in mitigation, they are the only class that is stuck with a 40% mitigation unless they glyph. DKs are the obvious winner with maximum mitigation on top of stun immunity.
Now lets look at the secondary static mitigation abilities
Druids: Barkskin - 20% less damage for 12s 1m cd
Paladins: Divine Protection - 20% less damage for 10s 1m cd
DKs: Bone Shield - 20% less damage until 3 charges of Bone Shield are spent (time varies), 1m cd.
Warriors: Shield Block - increases chance to block by 100% for 10s, 30s cd.
Warriors get the small end of the stick here. The better geared the Warrior, the less effective this ability will become for them. (Bad geared Warrior might have 25% chance to block making this ability 75% more effective where as a better geared Warrior may have 35% chance to block making this ability only 55% effective. Also, Warrior's cooldown is the only ability there that doesn't work on spell damage.
Now for the reactive abilities
DKs: Death Strike - Heals for at least 15% of DKs total HP or 30% of all damage taken for last 5s (which ever heals for more), also applies a shield that absorbs another 50% of the heal effect, modified by mastery. (Useful vs spells)
Warriors: Critical Block - Block has a chance to crit decreasing damage received by 60%, Mastery further increases it. (More uselessness vs spells)
Paladins: Holy Shield - increases Block chance by 15%. Their Mastery further increases Block chance. (Also useless vs spells)
Druids: Savage Defense - Each time you deal a critical strike while in Bear Form, you have a 50% chance to gain Savage Defense, reducing the damage taken from the next physical attack that strikes you by 75% of your attack power. Mastery increases chance and amount absorbed. (useless vs spells)
DKs are the only ones that have an ability that works with spell damage. I assume they'll be DSing every 5s or so what with the crazy rune regen they'll be getting from the RS procs now that RS is spammable.
Now for the bonus survivability round!
Paladins:
Ardent Defender - 20% less damage for 10s and will be brought back to 15% HP if it's up during an attack that would have otherwise killed you. 3m cd
Word of Glory - 60% more heals on Word of Glory and any overheals applies shield.
Sacred Shield - You know what it does. Mostly only useful when no Holy Pallies in raid.
6% more healing recieved.
Warriors:
Blood Crazed - 10% chance per hit to heal 7.5% of your HP over 5s.
Field Dressing - 20% more self heals and 6% more healing received.
Impending Victory - Chance to use VR when target is below 20%, heals for 5%
Last Stand - 30% more HP for 20s, 3m cd
Frenzied Regen - 36% healing over 10s, 3m cd
DKs:
Blood Tap - Heals for 15% of total HP, 30s cd.
Vamp Blood - 15% more HP and 25% more healing received for 10s, 1m cd
AMS - 75% less damage taken from spells based on total HP, 45s cd
Death pact - Heals 40% total HP consuming pet, 2m cd
WotN - 20% less damage taken below 35% HP and refreshes cd of BT and gives you a Blood rune, 45s internal cd
Dancing Rune Weap - Increases threat by 50%, increases damage by 50%, increases parry by 20% for 12s, 1.5m cd
Blood Parasite - 15% chance on melee to summon bloodworms that explode and heal.
Druids:
Regen - Increases HP by 30%, heals based on rage 20s, 3m cd
Couldn't find any more for Druids other than flat 12% damage reducing talent, dodge talents, and 10% hp increasing talent. Kinda stingy. I really don't know anything about Druids, so feel free to correct me. I have the other 3 tank classes though.