If you happen to read this before purchasing TiltShift or TiltShift Lite on the Mac App Store:

There is a small bug in version 1.2 that yields in wrong system requirements being displayed on the App Store page. TiltShift and TiltShift Lite do require OS X Lion (10.7.4) or later, despite the fact that the App Store lists 10.6.6 as requirements.

A version 1.2.1 update fixing this bug and featuring a few other improvements has been submitted to the Mac App Store on Dec. 28th for approval.