Originally Posted by Blizzard Entertainment
We are aware that there are many players who have issues dealing with Mage burst capabilities, however we feel that the main problem right now isn't simply Deep Freeze or Frozen orb directly, but rather the damage increase caused by Incanter's Ward. When stacked with other damage increasing effects such as procs and Frost Mage mastery, it can add up to an additional 30% damage multiplier, which can be quite devastating against many opponents. Because Incanter's Ward is one of the bigger reasons for high Mage burst, we have plans to make changes to it in patch 5.3.
In an upcoming change to the patch 5.3 patch notes you will see that we are looking to change the maximum spell damage increase from 30% to 15% but have the effect duration increased to 25 seconds, up from 15 seconds. This will lower the damage coming from Frozen Orb, Frost Bomb and other skills during a Mages burst window, but that damage multiplier will just last for a bit longer.