One of the most talked-about developments at the Microsoft Mix09 conference has been SketchFlow. Inspired by concepts popularized by Bill Buxton, Microsoft Principal Researcher and author of "Sketching User Experiences", SketchFlow enables iterative development via the incremental refinement of low-fidelity mockups, integrated directly into the design tools (Microsoft Expression).
Below is a picture I snapped during Christian Schormann's session where he gave a great demo of SketchFlow in action.
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