Apple's new iOS 4 for its mobile devices contains a number of new features, and is recommended by Apple for all iPhone and iPod Touch users; however, a number of people have reported a few problems with the upgrade. These problems include the install not completing, along with long and stalled backups.
CNET Editor Lance Whitney has outlined some of these problems, and provides a small step-by-step procedure for preparing your system before upgrading your devices to iOS 4, which can help prevent these problems from occuring. If you are already experiencing problems after updating, you ay try restoring the device to a backup and running through the procedure Lance describes.
Lance's article is available here.