We won't be supporting the x64 WoW builds because it's really not worth the effort to maintain two completely different versions of the game. (Addresses become very daunting to update each patch, and we'd have to do extra reversing and handling just to support the x64 client) The worst part about us supporting the x64 client, would be a drastic increase in memory usage from HB itself. (We'd have to store things in a way that the x64 client wouldn't get angry with)