In an email to registered developers, Apple informs them that it has opened subscriptions for iTunes Match beta. iTunes Match is the new service that Apple will be releasing alongside iCloud when it goes public with iOS 5 later this month, hopefully.
iTunes Match is the service that stores your music library in iCloud and allows you to enjoy your collection from anywhere, any time, on your iPhone, iPad, iPod touch, or computer. Any of your songs, including music you've imported from CDs, that matches with the 18 million songs in the iTunes Store will become available in iCloud and will play back at iTunes Plus quality (256 kbps DRM-free AAC), even if your original was of a lower quality.
To get started with iTunes Match, you need to download iTunes 10.5 beta 8 which was released only for Mac day before yesterday. Once downloaded, subscribe to iTunes Match by choosing Store > Turn On iTunes Match and clicking "Subscribe for $24.99."
If you have previously subscribed to iTunes Match, you just need to update to iTunes 10.5 beta 8 and start using iTunes Match once again. Please bear in mind that after the beta period ends, all iCloud libraries will be deleted. So even if you have added music to iCloud using iTunes Match, don't delete it from your computer.