So, OK, it's one thing going to some lengths to point out the limitations of PowerPoint, but what are the viable alternatives?
There are a few options.
In Edward Tufte's booklet, The Cognitive Style of PowerPoint, he argues that PowerPoint is especially dangerous when trying to communicate complex information. His examples were rocket science (specifically the review of damage sustained to the Colombia shuttle prior to it's destruction on re-entering the atmosphere, which could have prevented the accident) and medicine. In these cases, he goes on to argue, one should use a clear written report, and not rely on any projected visual aides which might distract attention from the all-important-detail. Fair enough, but what about the other 95% of presentations?
Assuming one has decided that slides are the way to get your message across (think twice), there are a couple of options. Eric Meyer has developed a Simple Standards-based Slide Show System (called S5), which allows for the presentation of content in a browser. I'm pretty sure that Sir Tim Berners-Lee used this technique at the talk I attended back in March. It's very simple, very basic, and does the job. It's decidedly low on the eye candy though, so if you want the wow factor you might want to look elsewhere.
Apple's Keynote (Mac only, I'm afraid) is proving robust. It's very easy to use and looks fantastic. It's tempting to fall into the trap of adding effects and transitions just for the sake of it though, as they do illicit oohs and aahs from the audience. But if you can resist the temptation you can leave the audience remembering your message rather than the transitions...!