Apple Announces iCloud Backup Reset on September 22nd

Apple has announced to developers that it will perform an iCloud Backup data reset on September 22nd.

iCloud Backup Reset
On Thursday, September 22, the iCloud Backup data will be reset. Backing up to iCloud or restoring from an iCloud backup will be unavailable from 9 AM PDT - 5 PM PDT. If you attempt a backup or restore during this time, you will receive an alert that the backup or restore was not successful. After this reset, you will be unable to restore from any backup created prior to September 22. A full backup will happen automatically the next time your device backs up to iCloud.

It's thought that this backup reset may be followed by iOS 5 GM seed.