Rebuilding iPhoto library causes issues with iTunes photo sync
Hopefully you have the run of the mill, the iPod Photo Cache is now stale issue which is easily remedied.


iTunes: Understanding the iPod Photo Cache folder - TS1314


Since you are on Mountain Lion, this is just a folder in the "iPhoto Library" and you can right click on it, and show package contents. Just drag that folder to trash and then quit both iPhoto (and Aperture if you have it) as well as iTunes.

A re-launch of iTunes should see that the folder is missing and clear any sync tokens, and proceed to rebuild a list of pictures, albums and events. Usually, there isn't a second step needed as this folder is designed to be safe to delete at any time to save space on a drive and exists to speed up syncing.

As always, kicking off a backup when looking into deleting things is never a bad idea in case the corruption is deeper than expected or just a sign of a failing storage device.