Stephan - You did an excellent job of harnessing Microsoft's style of design. I wouldn't be surprised if this were already a part of Windows.
CMD - The links aren't working for me! In fact, your entire sketchpad site is down, or at least for me. The description for your work is quite a read! Even without seeing the work, I can tell that it's going to be amazing. I can't wait to see it. Good concept btw. I'm always misplacing my minions and unevenly distributing punishment when I try to conquer the world...
Sabrown - You're very good at selling your product; you had me convinced that it is already on sale and that I needed to buy it immediately. I really like the layout you have constructed, and I know many people who would benefit from such a simple OS. My only problem with it would be the color scheme. Honestly, it's quite boring, and it lacks contrast. I recommend using Colour Lovers to choose a good color scheme. Although those palettes are really for Illustrator / Photoshop, you can easily adapt them to PDN.
Mike - A touch screen PDN in general would be amazing, really. I love your writeup, but the skinning itself isn't too amazing. Simple, yes, and a good concept, but not much of a "wow factor."