The editor hangs up, requiring a forced quit, with any antialiasing enabled in quality settings. It happens only when toggling the screen view. This is with indie 4.5.2f1 on a MacAir with Mavericks. (If I build a web player version, it has AA on fullscreen but not the window, as others have noted, and does not crash.) The system console log has some interesting notes at the end:
8/4/14 1:40:22.589 PM Unity[4012]: NSSoftLinking - The DataDetectors framework’s library couldn’t be loaded from /System/Library/PrivateFrameworks/DataDetectors.framework/Versions/A/DataDetectors.
8/4/14 1:40:22.589 PM Unity[4012]: NSSoftLinking - The function ‘DDMenuItemGetActionUTI’ can’t be found in the DataDetectors framework.
8/4/14 1:41:03.360 PM Unity[4012]: *** WARNING: -[NSImage compositeToPoint:operation:fraction:] is deprecated in MacOSX 10.8 and later. Please use -[NSImage drawAtPoint:fromRect:operation:fraction:] instead.
8/4/14 1:46:55.509 PM com.apple.launchd.peruser.502[173]: (com.unity3d.UnityEditor4.x.173392[4012]) Exited: Killed: 9