We’ve got a few discussions actively going on the tanking and dps changes in PTR 3.22. I think PvPers will like the bone shield cooldown being reduced to 1 min too. MMO-Champion has done a spell comparison with very promising results.

Ghostcrawler has commented now, read the discussion.

Death Knight
Blood

• Heart Strike now has its total damage increased by 10% for each of your diseases on the target to the primary target, and half that to the secondary target.
• Vampiric Blood now lasts 10 sec. (Down from 20 sec.)
• Subversion now also affects Scourge Strike.

Frost

• Frost Presence now reduces damage taken by 8%. (Up from 5%)
• Threat of Thassarian now also affects Rune Strike.
• Unbreakable Armor now increases your armor by 25% and increasing your Strength by 10% for 20 sec.

Unholy

• Bone Shield cooldown has been lowered from 2 min to 1 min.
• Dirge no longer affects Obliterate.

Tier 9

• Item – Death Knight T9 Tank 4P Bonus – Decreases the cooldown on your Unbreakable Armor, Vampiric Blood, and Bone Shield abilities by 10 sec. (Down from 20 sec)

Glyphs

• Glyph of Scourge Strike – Your Scourge Strike increases the duration of your Blood Plague and Frost Fever on the target by 3 sec, up to a maximum of 9 additional seconds. (Old – Your Scourge Strike has a 25% chance to cause Blood Plague and Frost Fever.)
• Glyph of Unbreakable Armor – Increases the armor granted by Unbreakable Armor by 20%. (Old – Increases the amount of damage absorbed by Unbreakable Armor by 20%.)
• Glyph of Vampiric Blood – Increases the duration of your Vampiric Blood by 5 sec. (Down from 10 sec)