The first member of Apple's iCloud family that requires separate payment is here: the $24.99-a-year iTunes Match. The service will store any and all music in your computer's iTunes library up to Apple's servers and make it accessible to any of your iOS devices or computers running iTunes.
Though the free iTunes in the Cloud has existed since the launch of iOS 5 on Oct. 12, that service only covers music you've bought through the iTunes Store.
Apple's iTunes Match examines your song collection and determines whether Apple's servers contain a copy of each tune, in which case no upload on your part is required, and you can download a high-quality 256 Kbps AAC iTunes Plus version of the songs onto any device or computer you've signed into using the same Apple ID.
But for those who still have lingering questions about iTunes Match, here are a few more details: