Google announced Google Music beta as cloud-based music service at Google I/O event day one. With Google Music beta, user can upload up to 20,000 personal music and sync it to listen from web browser or from Android device with Music app. You can pin recently played songs with offline caching in order to play it offline
New playlist feature called Instant Mix was available to automatically create playlists based on sound of current song preference. Music Manager desktop application for Macs and Windows PCs allows you upload music from from iTunes library, Windows Media Player library, My Music folder, or folders of your choosing to the cloud to play it online.
Music beta player supported playback on computer using browser including Google Chrome, Firefox, Safari, and Internet Explorer 7 and above and supported Android device running Android 2.2 and above with OpenGL2.0.
Currently it is only available on an invitation basis and only in US. Visit music.google.com to request an invitation to Music Beta by Google.
Google Music beta is free but Google hinted that it might start charging after the beta period ends. While Google Music in beta period, you can contact Google Music Beta with email address associated with Music Beta to feedback for product support or you can refer to Google Music Beta Help which contain some useful articles related to hot to use and troubleshooting.
Below is the video to introduce Google Music Beta down by Google