I am using iPhoto 9.4.2 under Mountain Lion 10.8.2. I am unable to import photos into my iPhoto library anymore. This happens both with photos already on my disk and photos from web pages.
After I start to import, iPhoto hangs with "Import Preparing to import..." in the top of the iPhoto window.
I have used all 4 steps in Photo Library First Aid (including Rebuild Database) without resolving the problem.
I tried using iPhoto Library Manager to rebuild the library, but this app launches iPhoto and starts an Import which hangs (I left it alone for several hours without any progress shown for importing events).
My iPhoto Library is 11GB in size. I have 22.5GB free on my boot drive. My iMac has 8GB of RAM.