iPhoto ’11 is an incredible update to Apple’s casual photo managing/editing suite which makes organizing and tweaking your digital snaps simpler and more streamlined than ever, but only if iPhoto ’11 doesn’t gobble up your existing library as part of the upgrade process… a mishap that is striking an alarming number of upgraders.
Here’s what’s happening: for some users upgrading from iPhoto ’09, the process of updating your existing library to be compatible with iPhoto ’11 is causing data loss. Sometimes, that’s just a few photos here or there; othertimes, it’s the whole honking library.
The best thing to do before you upgrade, then, is backup your existing iPhoto library. If you’ve already bit the bullet and upgraded and are one of the unlucky users who have lost photos, you can try to rebuild your permissions in disk util, then deleting the iPhoto preference file (com.apple.iPhoto.plist) in your User/Library/Preferences folder. After that, launch iPhoto with the Command and Option keys pressed, and rebuild your library. Hopefully that will sort you out.