Best Buy has launched an upload-based music streaming service.
Best Buy Music Cloud will upload music only from an iTunes library and make it available for streaming from the cloud via a web-based player (screenshot below) or iOS, Android and BlackBerry Apps.
You need to install an app on a Windows or MacOS machine to scan your iTunes Library and select songs for upload.
However, there are conflicting reports on app availability and service features. The Music Cloud site isn't much help, either, providing no information about what the Premium service costs or its features.
This DigitalTrends report says that the free service lets you listen only to the first 30 seconds of a song. You need to sign up for the $3.99 / month "Premium" service to listen to entire songs. The service uses Play Anywhere technology from Catch Media.