Google Play announced! Android Market, Google Music and the Google eBookstore will become part of Google Play. On your Android phone or tablet, the Android Market app will be upgraded to the Google Play Store app over the coming days. Your videos, books and music apps (in countries where they are available) will also be upgraded to Google Play Movies, Google Play Books and Google Play Music apps. The music, movies, books and apps you’ve purchased will continue to be available to you through Google Play—simply log in with your Google account like always.
Know more: Introducing Google Play: All your entertainment, anywhere you go.