Apple has just seeded a 3rd beta of iTunes 10.5.1 to the developers community with performance enhancements and some stability improvements. The latest beta, which is now available on the iOS Developer Center allows for further testing of iTunes Match. Apple reportedly wiped all existing iTunes Match libraries stored in iCloud earlier today to “prepare for the launch of iTunes Match“.
The Beta 3 Release Notes warn that Apple may again wipe iTunes match data during their ongoing testing (via MacRumors).
iTunes 10.5.1 beta 3 includes a number of important stability and performance improvements for iTunes Match, and is a required update for all subscribers to iTunes Match beta.
Backup regularly and do not delete the music you add to iCloud from your computer. Apple may periodically delete all iCloud libraries during the beta period. This will require you to scan, match, and upload songs again
iTunes Match beta is currently available to iOS developers only in the United States. For those who aren’t aware, iTunes Match is Apple’s $25/year subscription service that will match your existing iTunes library with 256-Kbps versions in the iCloud.