Check out the Unholy Death Knight changes that went live in the latest Patch 10.0.7 build.

Death Knight

Unholy

Harbinger of Doom – Sudden Doom triggers 30% more often and, can accumulate up to 2 charges, and increases the damage of your next Death Coil by 20% or Epidemic by 10%.

Defile – If any enemies are standing in the Defile, it grows in size and deals increasing damage every sec. Every sec, if any enemies are standing in the Defile, it grows in size, dealing increased damage, and increasing your Mastery by 1%, up to 8% damage.

Defile is no longer a choice node with Unholy Pact and has replaced Pestilent Pustules in the specialization tree.

Ruptured Viscera – When your ghouls expire, they explode in viscera dealing [ 10.6% of Attack Power ] Shadow damage to nearby enemies. When your ghouls expire, they explode in viscera dealing [ 11.6% of Attack Power ] Shadow damage to nearby enemies. Each explosion has a 25% chance to apply Festering Wounds to enemies hit. 

Feasting Strikes – Festering Strike has a 15% chance to generate 1 Rune and grant Runic Corruption.

Commander of the Dead now applies to any summoned ghoul or gargoyle, regardless of their distance from you.