Working on a Windows 8 app here at work, on 8th day now into project, using HTML5/CSS/WinJS, I'll tell you right now there is a huge learning curve for this. Much more than I anticipated. If Microsoft made HTML5 a way to make applications to "woo" web developers, we need videos(à la Silverlight TV) about Windows 8 development ASAP.
Or they're going to get frustrated on day one wondering what "HTML fragments" are and they'll quit. =)
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