Keepers:
Thorim's lightning 'only' hits 8 people now.
Mimiron's rockets won't kill melee running from shock blast or barrage anymore.
Mimiron can't shock blast AND barrage at the same time anymore.
Mimiron's mines do less damage and take time to arm now.
Freya water adds are now kickable.
Elder Stonebark doesn't gib melee as fast as he used to.
Vexax:
Straight up nerfed in 10-man (who cares).
Yogg:
Pets no longer fuck your raid when they hit a crusher in P2. (good change)
Adds have less health (nerfed before world first kill)
Death Ray no longer hits players who are under the effect of Malady of the Mind (Good, fewer RNG deaths).
Guardians of Yogg-Saron no longer use Dominate Mind (oh noes not a P1 nerf)
Guardians spawn slower (l2 force spawns if it's too slow for your guild's kill)
Guardians will no longer spawn if a player that is protected by Hodir’s Flash Freeze hits an Ominous Cloud (if you need flash freeze in P1 I don't know what to say to you)