Originally Posted by MMO-ChampionItem - Mage T16 2P Bonus (New) Arcane Missiles causes your next Arcane Blast within 10 sec to cost 25% less mana, stacking up to 4 times. Consuming Brain Freeze grants 1 charge of Fingers of Frost. Consuming Pyroblast! increases your haste by 750 for 4 sec, stacking up to 5 times.
Item - Mage T16 4P Bonus (New) Arcane Missiles has a 20% chance to not consume Arcane Missiles!. Consuming Brain Freeze has a 75% chance to drop an icy boulder on your target. Fireball and Pyroblast have a 10% chance to cause Inferno Blast to have no cooldown for 6 sec.
Looks like some interesting set bonuses for once.
PTR notes June 20:
Frost Bomb now deals 70% damage to players (up from 60%).
Living Bomb now deals 85% damage to players (up from 70%).
Nether Tempest now deals 85% damage to players (up from 70%).
Temporal Shield now also reduces damage taken by 15% while active in addition to existing effects.
Glyph of Blink now increases distance travelled with the Blink spell by 8 yards (up from 5 yards).
Glyph of Remove Curse now increases the damage dealt by 15% after successfully removing a curse (up from 10%).
Glyph of Spellsteal now heals the Mage for 5% of their maximum health after successfully stealing a spell (up from 3%).
Mastery: Frostburn has been redesigned. Fingers of Frost now increases the damage of Ice Lance by an additional 2%, Brain Freeze increases the damage of the instant cast Frostfire Bolt by 2%, and damage done by the Mage's Water Elemental is increased by 2%.