Apple notes that iTunes 8.2 now supports iPhones and iPod touches equipped with the iPhone 3.0 software update. Other accessibility improvements and bug fixes have also been made.
Jailbreakers beware: Apple also improved security in iTunes 8.2. According to a notice, Apple has improved bounds checking in 8.2 to prevent a stack buffer overflow problem that could lead to unexpected app termination or arbitrary code execution.
Today's iTunes 8.2 update changes the way your computer talks to the device. This affects things like QuickPwn and PwnageTool when they try to identify what's connected. Also, ssh over usb breaks due to same reasons. Fixes are in the works but for now avoid 8.2(These are probably *not* anti-jailbreak maneuvers, just Apple changing protocols that normally only Apple cares about.) To fully uninstall iTunes 8.2 on Mac, close all iTunes and do this from Terminal.app. Do NOT mistype it .. https://twerbose.com/t8791
iTunes 8.2 Update == Bad. It will check the hash of newer firmware images, call the mothership when restoring to beta firmwares, have updated MobileDevice so programs like QuickPwn and anything else that uses MD will get messed up, make sure your device has the correct security epoch, chipid, security domain, production mode, board id, bb chip id, etc. They can all be patched, but for now, hold back from updating.
If you install iTunes 8.2, QuickPwn and PwnageTool will not be able to talk to your phone correctly. You can always jailbreak with iTunes 8.1 or iTunes 8.2 prerelease for beta 4.