Project Blackstone Domain Registered By Blizzard

The domain name ProjectBlackstone.com has been registered by Blizzard leading to speculation about what the developer could possibly have up its sleeves.

It could have something to do with the upcoming Diablo III expansion which has been promised, but not detailed. Or it could be something entirely new inside the world of Blizzard, although that seems less likely. What do you think it is?

[via Fusible and PC Gamer]