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Each Blu Ray drive for the PlayStation 3 will cost Sony over $100, according to information The Inquirer discovered at the Games Developers Conference Europe. This is very expensive considering a DVD+RW drive is under $50. Microsoft can probably purchase these for under $50 because of the quantity they purchase.
Blu Ray technology is much more advanced. It is backwards compatible with DVDs and CDs and can store 25GB per layer. The advanced technology is cool, but it will cost you a bundle.