It's the same deal as the Nirvana - Nevermind (Super Deluxe) edition from a few months ago. When you order the CD version of Adore by The Smashing Pumpkins that has 16 tracks on it for £2.99, you receive the 89 track Super Deluxe Edition Autorip MP3 album for free. This version has all sorts of b sides and rarities like their Christmas song(!), tracks that only ever appeared on soundtracks, and remixes. Amazon are charging £28.49 for the MP3 album on its own!