I mainly play WoW on my Windows PC, but I do have it installed on my MBP in case I want to play on the go. I recently updated the game with the new WoD patch and was running around Stormwind with the normal so-so FPS (20-30 in a busy area with vsync on) at 1080p (external LCD). Well, after my Yosemite update last night, I ran around Stormwind again, with the same graphics settings and it was 46-47 FPS. Much better! Remember this isn't on the MBP's native LCD res, but on an external 1920x1080 LCD. Diablo 3 seemed about the same, maybe slightly slightly better.