https://support.apple.com/kb/DL1426
iTunes 10.4 is now designed for OS X Lion. You can now use iTunes with OS X Lion's new full-screen app capability, which allows you to use iTunes and other apps without distractions. Navigate between your full-screen apps with a simple gesture.
iTunes 10.4.1 provides a number of improvements, including:
Fixes a problem where the media keys on some third-party keyboards work inconsistently with iTunes
Addresses issues with adding artwork to songs and videos
Resolves an issue which may cause iTunes to become unresponsive when purchasing an HD movie
Fixes a problem where iTunes may take longer than expected to open after waking your Mac from sleep
Addresses issues with VoiceOver support
