Guy Kawasaki's 10/20/30 Rule of PowerPoint

I've been reading up a fair bit on presentation techniques recently. There are a ton of resources out there, such as Presentation Zen, with tips and techniques. I have come to the conclusion that most of my presentations use too much text and too many slides (and I'd bet that the same is true of your presentations). I am setting a goal for myself to improve my presentations in 2006. While I'm not sure how feasible this is in all situations, I was intrigued by Guy Kawasaki's "10/20/30 Rule of PowerPoint," which he defines as the fact that "a PowerPoint presentation should have ten slides, last no more than twenty minutes, and contain no font smaller than thirty points" - especially "for any presentation to reach agreement: for example, raising capital, making a sale, forming a partnership, etc."