Apple TV 3 is updated to latest firmware as of today April 2 2015. iCloud photos will not load photos. It keeps searching.

Try the following steps, check whether things are working after each step where appropriate, before trying the next.

1. Log out and back into iCloud
2. Restart the Apple TV (Settings > General > Restart).
3. Restart the Apple TV by removing ALL the cables for 30 seconds.
4. Restart your router. (Also try removing it’s power cord for at least 30 seconds)
5. Reset the Apple TV (Settings > General > Reset > Reset all settings)
6. Restore the Apple TV (Settings > General > Reset > Restore)

I logged out of iCloud, restarted, logged back into iCloud, then went to screen saver and went to my photos. I waited for the photos to load (the count of each folder) and then chose my album. It took about 2 minutes to load my photos and begin the screensaver.

Thank you very much. This helped on the first step.