I would have mentioned - <a href="http://www.uistencils.com" rel="nofollow">http://www.uistencils.com</a> - the new whiteboard tool is perfect for the non-designers to iterate fast.
Interesting...just yesterday, I was attempting to wireframe an idea I had and found myself hopelessly lost (I'm not a designer). While in the past I generally used quick sketches, it looks like you advocate a more detailed approach to wireframes, where they almost look like the finished product on paper. How do you trade that off with rapid iterations and the time needed for re-drawing detailed drawings?