Apple’s Apple TV Team has sent out an email advising Apple TV to upgrade immediately:
If you’ve installed the Apple TV 3.0 software update, you should immediately update to version 3.0.1. This prevents content from temporarily disappearing until it is resynced.
To update your Apple TV software:
1. Reboot your Apple TV (unplug the power cord and plug it back in)
2. Select Settings > General from the main menu
3. Select Update Software
4. Select Download and Install
Note: Your Apple TV will conduct a restart, which is followed by the Apple logo and a status bar.
For more information, please refer to Apple’s support article (TS3116) here.