A fix for an issue in which photo libraries are blank or missing after the update to iPhoto ’11, and all of the contained images are apparently deleted, is reportedly imminent.
A post from Liz Castro, one the first users to report this issue, states:
“They confirmed that there was indeed a window during the updating process in which a force quit could ‘create data loss.’ I asked if changing permissions of the iPhoto Library was really helpful (as someone suggested on one of my blog posts), and was told that it was only part of the solution. Mostly, and this was the most important thing, they told me that a fix from Apple was imminent.”
In the meantime, users should likely avoid updating to iPhoto ’11, or ensure that their photo libraries are backed up prior to doing so.