The new update comes one month after version 9.3 brought enhancements to Apple's photo management software that included tighter integration with professional-level photo editor Aperture, AVCHD support and a new Export option, among others.
From the release notes:
- What's New in Version 9.3.1
- Addresses a problem during the migration of albums from MobileMe Gallery that may cause photos to be moved from their original events into a new event called "From MobileMe"
- Fixes an issue that in rare cases could cause iPhoto to hang when upgrading libraries
iPhoto version 9.3.1 weighs in at 599.65 MB and can be downloaded through Apple's Support Downloads Page or Software Update.