Apple has finally turned on its iTunes Match service after a two- weeks delay. iTunes Match is a $25-a-year subscription service that allows users to Store their entire music library in iCloud including music they've imported from CDs, and enjoy their collection on their iPhone, iPad, iPod touch, computer, or Apple TV.

iTunes Match was introduced as part of Apple's iTunes 10.5.1 software update. Songs that are not recognized can be uploaded automatically. The service promises to function with multiple computers used by the same person by eliminating duplicates.

Supported OS are Windows XP/Vista/7 and Mac OS X 10.5.

Apple had initially said that the service would be available by the end of October.

iTunes 10.5 also included:

- iTunes in the Cloud. iTunes now stores users music and TV purchases in iCloud and makes them available on their devices anywhere, any time, at no additional cost.
- Automatic Downloads. Purchase music from any device or computer and automatically download a copy to a Mac and iOS devices.
- Download Previous Purchases. Download past music, TV, app, and book purchases again, at no additional cost. Previous purchases may be unavailable if they are no longer on the iTunes Store.
- Sync with an iPhone, iPad, or iPod touch with iOS 5.
- Wi-Fi Syncing. Automatically sync an iPhone, iPad, or iPod touch with iTunes any time they're both on the same Wi-Fi network.

iTunes 10.5.1 also addresses a security issue. Until now, during iTunes periodical checks for software updates, a man-in-the-middle (attacker) might offer software that appears to originate from Apple. This issue has been mitigated by using a secured connection when checking for available updates. For OS X systems, the user's default browser is not used because Apple Software Update is included with OS X, however this change