WoW is allowing them now.
The move was obvious according to some, as you'll be allowed to create level 55 deathknights on any server you want regardless of whether your qualifying character is on a pve server currently or not. So the whole notion of needing to level from the ground up was thrown out of the window anyway.
Good idea on Blizzard's part because, whatever the cost, it may get some to think twice about spending money on warhammer around the same time they'll spend money to transfer.
This was one of a few holdouts Blizzard's given in on though. If I were to name the posts that receive the most Blue "we aren't considering it at this time","we have no plans to change this at this time" it would be:
2)Flying Mount Costs
3)PvE to PvP transfers
Not that one has anything to do with the other, but forum prepare thyself for the onslaught of "You changed your mind on xfers, now lower the cost of flying mounts".
A new World of Tanks?
1 day ago