I was wondering this, too. After reading a similar post for the Windows versions, I confirmed that if you uncheck the fullscreen option under the graphic options, and have your game resolution set a bit less that your screen resolution, the game will run in a window, and you will be able to switch to other applications.
Not as good as running in fullscreen and being able to command-tab to other apps (or three-finger swipe to other windows/full screen apps). Maybe that's an upcoming feature!