iTunes 9 hasn't made it into Software Update yet but you can still download it via the Apple site right here. If you are already jailbroken iTunes 9 doesn't appear to interfere with you at all. Not sure if it interferes with the jailbreak process yet however.
Lots of new features. Read here and here for more details on the features. We'll get a full review up ASAP!
- In-iTunes iPhone and iPod Touch App Management (yes!!!)
- Improved Syncing Options
- Genius App Recommendations (could be neat)
- Genius Mixes
- Share via Twitter and Facebook (for you social networkers)
- iTunes LP Enhanced Album Content (snazzy toy)
- DVD-style Movie Extras (snazzier toy)
- New, Redesigned Store (sexy looking)
Update: You should see iTunes 9 in Software Update now