In response to your answer in the latest issue of Shutterbug when asked why digital projectors don't project in a square format.
I run digital slide shows all the time. I have a Photoshop action that sizes all my images to 1024x768 and adds the necessary black borders so both horizontal and vertical images fill up the screen, without any extraneous visual clutter. The black borders act like a slide mount and are virtually invisible in a dark room. Granted, the verticals are approximately 33% smaller in long dimension, but it's still visually pleasing to watch.
Thanks for the web design plug...