I see Microsoft has announced their Retail Experience Center (REC). I've been there, and I can definitely say they've built something really cool. In fact, they've included so much detail it's actually kind of surreal. You can easily forget you're not in a real store. Right down to the giant mural of a parking lot that's behind the sliding glass doors. Anyway, if you have the means, I recommend checking it out.

Also, Avanade's retail demo is installed on their Microsoft Surface, and you can catch a glimpse of it in the video (it also appears in one of the gallery images). So that's cool to see! :)