Apple’s new Cloud-based music storage system has a few “gotchas”.
Apple’s iTunes Match allows users (for $29 per year) to upload their music collection to Apple’s cloud – except Apple doesn’t actually upload the music. Instead, iTunes Match will see if the tune already exists and use that 256Kbps AAC file for you. It will only upload your tune if it does not exist in their library already.
In the process though, iTunes Match will remove all your tunes from your device when you turn on this service. What does this mean? It means that if you do not have a WIFI or 3G connection you will not be able to download and play your tunes unless they have already been downloaded.
Those tunes that are required to be uploaded could take some time, and there’s also no intuitive way to manage your collection on your device, such as deleting tracks or playlists so beware before removing any tunes after turning on iTunes Match.