Tom Chilton, the lead designer on Activision/Blizzard's mighty World of Warcraft MMO has hinted at and then killed the idea of a free-to-play version of the game."If another game comes along and blows us away it may not make sense for us to have a subscription fee. Or even further down the line, when we have another MMO out", he tells PCG.
However, don't get your hopes up quite yet, "We’re not spending a lot of time thinking about it. It’s not something that’s a reality for us in the near future", his his conclusion.
Source:
PCG