Right now the only way to get antialiasing is to play the game in a web player or dashboard, as full scene anti aliasing is enabled in those. It's been requested for the regular players as well. -Jon
For beautiful antialiasing, build your app from unity to a windows PC target and using the nvidia GeforceFX's control panel force teh Antialias to 8x and enjoy Is there such an option to force AA in OSX?