I've a very large photo library (more than 20.000 pics). Aperture 3 is every day slower, i've read and apply all the suggestions from various site to fast up the app (that runs on new iMac or new MBA). I'm thinking to come back to iPhoto that seems more light and user - friendly. I know here and there most users move from iPhoto to Aperture ... Just wonder: iPhoto 2011 uses non destructive editing like Aperture ? I know that if i simply rotate a pic Aperture NOT create a new photo but simply add somewhere the rotate effect PRESERVING original. iPhoto prior to 2011 version create NEW photo as a duplicate even if i want to simply rotate it. The new 2011 version change that in some way ? It's a pity if it creates a duplicate for every minus editing, in this way my 20.000 pics database will upgrade to 40.000 !!! I'm looking for an App to automagically sync my iPhoto library between iMac and MBA, anyone ?