Chief executive Steve Jobs said that iTunes 9 puts a greater emphasis on Apple's Genius analysis tool, and outlined a new Genius Mix feature which analyses a user's library and constructs up to 12 'channel' lists that continuously play similar songs from the library.
Also headlining the new version of iTunes is a multimedia feature known as iTunes LP, which allows artists and publishers to bundle multimedia content such as photos, artwork and lyrics into a digital album release.
While the new feature bears some resemblance to the menu and bonus material featured with many modern DVDs, Jobs said that iTunes LP traces its roots to the glory days of vinyl pressings.
"It was great because you not only got the music, but you got great photography, you got liner notes, and who could forget some of these classic albums?" he said.
"Unfortunately most of that left us when we went to CDs, and even more when we went to digital music, and that should not be the case. We can deliver amazingly rich content digitally, and that's what we're doing with iTunes LP."
The update also sports a new layout for the iTunes Store, along with a new 'home sharing' feature which allows users to share libraries with up to five machines on a home network.
For users with an iPhone or iPod Touch, iTunes 9 will sport a new management interface which will allow users not only to add and remove Apps, but to adjust the order and presentation of App icons on the iPod or iPhone screen.
The company said that the iTunes 9 update would be available immediately as a free upgrade.
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