The latest firmware update released by Apple may have improved security and added features, but some iPhone owners are having problems. Reports from users on the Apple support forums indicate a major problem with updating to iPhone OS 3.1 on the iPhone 3G.
Users are ending up with bricked phones, and iPhones that crash several times, requiring a hard reboot. Holding the sleep and home button doesn't always work, however. Some users are finding it necessary to downgrade to iTunes 8 and firmware 3.0.1 to solve the problems.