Why won't my iPhone sync all my photos?

Hi! Just recently, I switched to iOS6, and ever since then, my itunes won’t sync all of my photos to my iphone. There is enough storage space for it all, I’m doing it correctly (via the photos portion of itunes sync), and all software is updated, so why won’t it sync?
It worked perfectly fine before I installed iOS6, as well, so it can’t be a human error.
The sync will start normally, sync all music/videos/apps/etc, but when it gets to photos it only shows “syncing XX out of ~900 photos” instead of the ~4000 it should be syncing.
I’ve tried restarting my computer, restarting my phone, switching cables, and pretty much every simple solution I could think of, but to no avail! I’m getting pretty frustrated now, and I’m reaching out to you, Fluther! Please help!