This is one article where it's better just to enlarge the image above and read what's in the Collector's Edition for Diablo III. Of course, you could continue to read this in case you enjoy reading sentences.
Although Diablo III remains without a release date and no suggested retail price has been announced for the Collector's Edition, we now know that it will come in a large white box (as opposed to the basic standard black, it seems) containing the game for PC or Mac, a hardcover art book, soundtrack, behind-the-scenes DVD and Blu-ray two-disc set, a Diablo skull tchotchke, a 4GB USB in the shape of a soulstone, and a bunch of exclusive in-game content.
The previous report on Annual Pass World of Warcraft subscribers receiving Diablo III for free will likely not include the Collector's Edition as the copy of Diablo III in the deal is a digital download.