Will Amazon cloud service rain on Apple's parade?

Here's how effortless it is to move your digital music collection from Apple's iTunes software to Amazon's new Cloud Drive music service:

6. Download Amazon's separate Cloud Player app for Android to stream that music to your phone, or use a Web browser to listen to it from any PC.

The awkward stage of the digital music revolution

Welcome to the awkward stage of the digital music revolution. Online song sales have stagnated, depriving the endangered music industry of one of its last remaining lifelines. But digital music continues to be a vital battleground for Google, Apple and Amazon to try to lure users to their other devices and online offerings.

Now, Jeff Bezos & Co. have boldly tried to leapfrog Google and Apple in the quest to liberate people from the decade-old practice of buying and downloading digital songs to a computer and at the time manually transferring them between devices.

Thanks to the massive server capacity backing its successful cloud computing business, in which it rents computing power to other companies, Amazon can offer its streaming music users 5 gigabytes of music storage for free, or 20 GB if they buy just one album from Amazon. The company is as well prominently advertising the service on its home page.

"We observed from our other digital media businesses that buy-once, play-anywhere as a matter of fact resonates with consumers," Carr said.

The service Amazon released last week has been criticized for being difficult to use and incompatible with Apple iPads and iPhones.

What does the future of cloud music look like?

So what does the future of cloud music look like? Google, Apple or Amazon might after all get the major-label licenses that will allow them to make storing music collections in the cloud seamless for users. Or subscription music services just as Mog, Rdio and Rhapsody that offer unlimited access to a broad catalog of Web-based music for a monthly fee may find the mainstream success that has long eluded them.