As noted by 9to5Mac, Apple has just released an update to iTunes. iTunes 11.0.5 is a minor update which addresses issues with iTunes in the Cloud, and is available immediately through Software Update via the Mac App Store, as well as direct download from Apple’s iTunes website.
From the release notes:
This update corrects an issue with iTunes in the Cloud, where some purchases may download or play unexpected items.
For information on the security content of this update, please visit: support.apple.com/kb/HT1222.
The update addresses the same issue that Apple recently patched in iOS 7 beta 6, and requires no additional configuration to address potential problems.
