Statement by Blizzard:
While we can confirm that the game runs natively and takes advantage of the full screen resolution of the new MacBook Pro, we need to work harder to optimize it for window mode on the new system. We will offer an update for Mac players when we have more details to share.
Diablo III was cited as an example of a game with support for the Retina display of the new MBP in the opening keynote of WWDC 2012, but as you can see Blizzard wants to improve the thing even more – especially because, at 2880 × 1800 pixels, it can only run at 20-25 frames per second.[[AppleInsider]