Announced at yesterday’s WWCD2011 Conference, iTunes 10.3 beta (otherwise known as “iTunes in the Cloud”) is now available for use on your computer, iPhone, iPad, and iPod touch.

So how does iTunes in the Cloud work?

New music purchases from iTunes are automatically downloaded to all your Apple devices via 3G or Wi-Fi. Anything you’ve purchased previously from iTunes will be stored in your purchase history. Your past purchase history can be synched to your devices.

But obviously not all your music will have come from iTunes purchases. For music fans with big CD and download collections, iTunes in the Cloud is offering an additional service for $24.99 a year.  Our friends at Hypebot report:

Here’s how it works: iTunes determines which songs in your collection are available in the iTunes Store. Any music with a match is automatically added to your iCloud library at 256-Kbps iTunes Plus quality. With 18 million songs in the iTunes Store, most music is probably already in iCloud, but you can upload what iTunes can’t match. As Apple is quick to point out, that’s faster than Amazon or Google.

Click HERE to download iTunes in the Cloud beta.

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