Looks like someone made a boo-boo. Two weeks after the release of Apple TV 3.0, Apple has pushed out 3.0.1.

Symptoms

• You are using Apple TV software version 3.0 and all of your movies, TV shows, and songs appear to be missing,

  

or

• You are using Apple TV software version 3.0 and all of your movies, TV shows, and songs appear to be present, but you have not yet updated to Apple TV software version 3.0.1.

Resolution

There is an issue with Apple TV software version 3.0 that can possibly cause your content to disappear after a period of time. All customers running Apple TV software version 3.0 should immediately restart their Apple TV and then upgrade to Apple TV software version 3.0.1.

For either symptom, do the following:

1. Restart your Apple TV by unplugging the power cord and plugging it back in.
2. Select Settings > General from the main menu.
3. Select Update Software.
4. Select Download and Install when prompted.

   Note: Your Apple TV will restart; this is followed by the Apple logo and a status bar.

If the issue persists, try disconnecting your Apple TV from your computer, and then connecting it again. To disconnect and then reconnect a computer:

1. On your Apple TV, go to Settings > Computers.
2. Select your iTunes library to disconnect.
3. Select your iTunes library again to reconnect.

via Apple