With the release of iOS 5 coming tomorrow, iTunes 10.5 is now available is a software update for both Mac and Windows. This is needed for the iOS 5 update. Additionally, iTunes 10.5 brings with it support for iCloud, Apple’s new online cloud based storage service.
As for iOS 5, here are a couple of links for some information.
For new features in VoiceOver,
For new VoiceOver gestures and keyboard commands in iOS 5,