Today, when I saw the MIX keynote and saw the new Blend3 Sketch Flow, and when the guy went to the toolbar and picked a few buttons and text and put it on the form and then he went and changed something (couldn't see it clearly, but I think he changed the style) and then it looked like a normal button. This raised the question about having this kind of support (sketching RAD controls in Blend3) and hopefully being able to do prototype with RAD controls in Blend3!
..Ben
..Ben