Seth Godin Addressed This
Seth Godin is the internet marketer guru. He addressed this years in several blogs (http://sethgodin.typepad.com/seths_blog/2008/10/nine-steps-to-p.html) and a PDF e-book that he allowed to download for free once. His point is to use the power point as a cinematic extra that emphasizes the points of your lecture. I did this once for a creation science lecture I gave and it had a profound impact on the audience. What Toni says is basically in agreement with Seth.
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