Safari 5 dropped yesterday and its sibling, iTunes 9.2, is reportedly waiting for its turn. A gold master edition has been seeded to developers, signifying that it is as close to completion as it's going to get.
What can we expect from the update? Compatibility with new iOS 4, of course, and the updated file structure that the new firmware will include. We also expect it to allow for the iBooks syncing between devices and PDF support that Steve Jobs discussed at yesterday's keynote.
According to iPodNN, additional changes include faster sync times and faster scrolling through lists. When will it drop? iOS 4 is due on June 21st, so iTunes 9.2 should be released shortly before then.