Microsoft Press has published a new book for Windows 8 application programming with HTML, CSS and JavaScript. You can download the PDF version of the book free of charge. For the details please see Microsoft Press blog:

Free ebook: Programming Windows 8 Apps with HTML, CSS, and JavaScript
http://blogs.msdn.com/b/microsoft_press/archive/2012/10/29/free-ebook-programming-windows-8-apps-with-html-css-and-javascript.aspx

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AMB