Apple has updated the iPhoto app for Mac to version 9.6.1 in order to prepare for the upcoming move to the new Photos for OS X app.
What’s New in Version 9.6.1
• Improves compatibility when migrating iPhoto libraries to the new Photos app in the OS X Yosemite 10.10.3 (available this spring)
• Fixes an issue that caused iPhoto to display only the first 25 images in a Facebook album
• Fixes an issue that could cause iPhoto to become unresponsive when printing an image
The update is available via the “Updates” tab in the Mac App Store.