The following are articles in my Delicious library that include the tag "PresentationDesign."
Designing a narrative with index cards: From Communication Nation, a proven, low-tech approach to designing a presentation, either from the "top-down" or "bottom-up."
Designing slides: From Eye on Learning, a series of presentations, on and examples of, PowerPoint slide design.
"...Whip your Slides into Shape": From The Learning Generalist, ideas for both the design of the presentation itself as well as the slides as a vehicle for them.
How to Create a Presentation for Someone Else: From the Duarte blog, ideas on how to facilitate the process of designing a presentation someone else will deliver.