Revamped new iTunes 11 user interface hints at future of OS X
Integrating iCloud & Stores into your iTunes library
Transitioning to the desktop version of iTunes, Cue noted that new new version would be "dramatically simpler, and we've built iCloud right in," rather than being tacked on as a Sidebar item separate from the Library. Instead of managing your local files and your available downloads from iCloud in separate bins, you see all your content together, whether it's saved locally or not, similar to how iOS 6 now manages apps. To download iCloud content, you just click on the cloud icon.
In doing away with the Source List, Apple is now providing a consistent menu bar interface (borrowed from the original iTunes Store) for perusing your content, whether its local or stored in iCloud. It's the same multitouch-friendly interface used in the new iOS iTunes, iBooks and App Store apps.
Also built right in: Apple's iTunes Store. Instead of continuing as a textual database listing of your local content, iTunes 11 shows off your local music albums as icons full of songs, even using the iOS Folders user interface to represent the songs within in album (or the credits within a movie). Click a button, and Apple looks up Store content related to what you own, blurring the line between your content and the content that's available in the iTunes Store.
Also new: playlists. Rather than being constantly visible from the Source List, Apple handles these collections similar to iOS Folders as well, poping up a listing of your playlists whenever you drag content to provide potential targets. This provides the functional equivalent of the old Source List without dedicating a broad sidebar of the app to showing it all the time.
Apart from this selection feature, Playlists now appear only when you select them in iTunes' menu bar. To add songs to a playlist, you click the Add button and pick songs from your library, then click done.