[Music Beta by Google] Free and invitation-only for now. [Amazon Cloud Player] 5GB storage for free; $20/year for 20GB and $1000 a year for 1TB. Songs bought on Amazon don't count against the limit. [iTunes on iCloud] Free for iTunes purchased music. Apple offers an iTunes Match service that will match up non-iTunes songs with its library and upgrade them to 256kbps AAC DRM-free, and the iTunes Match songs are shareable with up to 10 devices. However, iTunes Match is a service that requires a $24.99 annual subscription [0] 
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