Although the fall XBOX Live update will add many features, it will also remove some too. Users who use third party memory devices will find those devices will no longer work with the XBOX 360.
"If you continue to use an unauthorized Memory Unit after the update, you will not be able to access your stored profile or saved games."
Xbox.com lists only Microsoft-made items and those bearing green "Licensed for Xbox 360" or white-and-green "Created by Xbox" labels as devices being supported.