I am not at MIX.  However, I have been wanting to write about these tools since the MVP Summit where I first saw the beta tools.  You can download all you need here.

Once installed, after clicking, file –> new project you should see:

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Highlighting windows Phone Application gives you this template.

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Should you decide to continue (and you should) you will see a split designer where you can drag and drop standard Silverlight controls onto the phone surface.

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Oh and, when you debug you get a nice VM which runs the Windows Phone 7 Series OS complete with battery warnings and all.  Stormtrooper not included.

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