About Wi-Fi music sync
You can use Wi-Fi® music sync on your BlackBerry® device to browse songs and playlists that are in your Windows Media® Player library or iTunes library on your computer. You can select songs and playlists that you want to download to your device, and when your device is within range of your Wi-Fi network or when you connect your device to your computer with a USB cable, the songs or playlists are downloaded to your device. You can also create and change playlists and synchronize these playlists from your device to your computer.
Songs and playlists from your computer are integrated in the Music application on your device. These songs appear dimmed if they have not yet been downloaded to your device. Within the Music application on your device, your Wi-Fi Music Sync list displays the status of your songs and playlists, such as pending or downloaded, as well as the status of your connection with the BlackBerry® Desktop Software.
You can only use one Wi-Fi music sync connection with one computer at a time.