Mages wield the elements of fire, frost, and the arcane to destroy or neutralize their enemies. They are a robed class that excels at dealing massive damage from afar, casting elemental bolts at a single target, or raining destruction down upon their enemies in a wide area of effect. Mages can also augment their allies' spell-casting powers, summon food or drink to restore their friends, and even travel across the world in an instant by opening arcane portals to distant lands.

According to Community Manager Bornakk on his post in the official servers, this move is being done to address faction imbalance issues in the game. Here's his exact post as taken from the forums:

To address faction imbalance issues on Oceanic PvP realm Thaurissan, we will be offering free character moves for Alliance players only from Oceanic PvE realms Nagrand, Aman'Thul, and Khaz'goroth to this realm.

This transfer opportunity will open on Thursday, June 12, and is scheduled to end no later than Thursday, June 19. During this timeframe Paid Character Transfers to Nagrand, Aman'Thul, and Khaz'goroth will be disabled as we focus on resolving the issue at hand.

In the event that we meet our transfer goals before the scheduled end date, transfers may be disabled without prior notice. No additional characters will be eligible for these free moves once the transfers have been closed.