Apple today released iTunes 10.5.1, a software update that officially brings iTunes Match to the masses for the first time.

Under the subheading “Available Now,” Apple states of iTunes Match:

A match made in iCloud.

With iTunes Match, even songs you’ve imported from CDs can be stored in iCloud. And you can play them on any iPhone, iPad, iPod touch, Mac, or PC — whenever you want and wherever you are, without syncing. iTunes Match is just $24.99 a year.

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 iCloud for you to listen to anytime, on any device. Since there are more than 20 million songs in the iTunes Store, chances are, your music is already in iCloud. And for the few songs that aren’t, iTunes has to upload only what it can’t match. Which is much faster than starting from scratch. Once your music is in iCloud, you can stream and store it to any of your devices. Even better, all the music iTunes matches plays back from iCloud at 256-Kbps AAC DRM-free quality — even if your original copy was of lower quality.

In order to purchase iTunes Match, you must first download and install iTunes 10.5.1 from within the iTunes application. From there, select “iTunes Match” on the left-hand of the screen and follow the directions.

First announced by Steve Jobs in June, the $24.99/year iTunes Match is pairs all your iTunes songs with iCloud, whether those songs were digital downloads or ripped from CDs. Once in iCloud, music is able to be streamed to any iDevice and stored at 256-Kpps AAC DRM-quality, even if the original song was of lower quality.

AppAdvice will provide a full review of the iTunes Match service later in the week.