Wait... what? Yep, but only "KINDA"... What you are about to watch is a MOD for Starcraft 2 called StarCraft Universe and it mimics gameplay like that of Warcraft. Kinda freakin' cool.
"Though StarCraft Universe will not be a full scale MMO, it takes the team oriented raiding style of World of Warcraft and combines it with many slasher action RPG elements of Diablo."
Due to come out any time now, which is obviously WAY before Diablo 3 (sigh).