Armed with licenses from the music labels and publishers, Apple will be able to scan customers' digital music libraries in iTunes and quickly mirror their collections on its own servers, say three people briefed on the talks. If the sound quality of a particular song on a user's hard drive isn't good enough, Apple will be able to replace it with a higher-quality version. Users of the service will then be able to stream, whenever they want, their songs and albums directly to PCs, iPhones, iPads, and perhaps one day even cars.
It's believed that Apple has paid dearly for its cloud streaming licenses and thus it's unlikely that the service will be free. It's suggested that Apple could include cloud streaming in its $99/yr MobileMe service.