(CNN) -- News that Microsoft has sunk $300 million into a venture with Barnes & Noble sends a clear signal that the computing giant and the bookseller aim to shake up the e-book market with new ammo in their fight against Amazon and Apple. But whatever impact the move has on sales of B&N's Nook e-readers now, it's the future of the partnership that has truly disruptive potential. The Nook's considerable catalog of books and other content could become more formidable when married with products like Microsoft's forthcoming Windows 8 operating system -- which is designed to run on tablet computers -- and even its leading game console, the Xbox.
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Microsoft's investment in the Nook expands options for Barnes & Noble e-books
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The Windows 8 operating system could benefit from the Nook's catalog
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Currently, Amazon dominates the e-reader and e-book marketplace
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Microsoft spent $300 million for 17.6% of B&N's e-book business
"What's happening right now is, Amazon is walking away with that business, because @placeholder already has the book buyer at a critical point: their website," McQuivey said.