Directly ripped from EJ forums:
Set Piece Bonuses.
ROGUE
(2): Your normal melee swings have a chance to Invigorate you, healing you for 90 to 110.
(4): Your Backstab, Sinister Strike, and Hemmorrhage critical hits cause you to regain 5 energy.
(6): Reduces the threat from your Backstab, Sinister Strike, Hemmorrhage and Eviscerate abilities.
(8 Piece): Your Eviscerate has a chance per combo point to reveal a flaw in your opponent's armor, granting a 100% critical hit chance for your next Backstab, Sinister Strike, or Hemmorrhage.
WARRIOR
(2): Increases the damage done by your Revenge ability by 75.
(4): Improves your chance to hit with Taunt and Challenging Shout by 5%.
(6): Improves your chance to hit with Sunder Armor, Heroic Strike, Revenge, and Shield Slam by 5%.
(8 Piece): When your health drops below 20%, for the next 5 seconds healing spells cast on you help you to Cheat Death, increasing healing done by up to 160.
Paladin:
Ring: 16int/sta 37healing 6mana/5 ring
2: Judgement of Light heals for an additional 20 points
4: -12m on LoH
6: Flash of Light and Holy Light have a chance to imbue your target with Holy Power(no idea what that is)
8 Piece: Your Cleanse spell heals the target for 100
Druid:
Hat: 25sta 31int 20SPI 59healing
2: Rejuv ticks have a chance to restore 60 mana, 8 energy, or 2 rage to the target
4: Mana cost of heals -3%
6: Cast + tick of Regrowth increases target HP by 50, stacks 7 times
8: Healing Touch crit = 30% mana back(5pc EF)
Priest set bonuses:
2 pc: Reduced mana cost of Renew by 12%
4 pc: On Greater Heal critical hits, your target will gain Armor of Faith, absorbing up to 500 damage
6 pc: Reduces the threat from your healing spells
8 pc: Each spell you cast can trigger an Epiphany, increasing your mana regeneration by 24 for 30 sec.
Warlocks:
2: -10s on CoDoom
4: shadowbolts cause vampirism(healing for 270-330)
6: 50% less threat on crits
8: 12% health cost redux on lifetap
Mage bonuses:
2: -1m on Evocation
4: Mage Armor gets +35resist vs. school when struck by a spell of that school
6: Damage spells have a chance to proc a +200 damage on next spell(s?)
8: Damage spells have a chance to proc no threat on next spell.