Sony is backing down on its proprietary music format and will open its media players to other, non-proprietary formats. 

In addition, the Japanese device manufacturer will shut down its digital music store, allowing users to download their tracks from anywhere.
Yesterday, Sony launched new Walkmans that are capable of playing music in a number of formats, including Windows Media Audio, MP3 and AAC.
Sony, whinch introduced the world to the concept of music on the move with the Walkman devices, lost market share to companies like Apple when the new digital format become popular.