Can I update to iTunes 9.0.2 with a jailbroken or unlocked iPhone?
Updating to iTunes 9.0.2 will not affect your current iPhone jailbreak or unlock. No news or advice has been posted by the official iPhone DevTeam on this subject. Jailbreak after installing iTunes 9.0.2 at your own risk.
Several new features for iPhone users have come to iTunes 9.0.2, now available from Apple as a free download. iPhone specific-improvements relate to app sorting and media syncing. Users can add or delete home screens and arrange apps directly in iTunes.