This is hardly a book at all, but is more of an essay. It is a wonderful summary of why one feels discontent and ill informed after sitting through a lengthy PowerPoint presentation. Tufte starts with a detailed accounting of the communication processes that led to the Challenger accident. He then proceeds into many common presentation flaws commonly made and he even includes some suggestions for compensating for those flaws.
Interesting tidbit: NASA engineers were required by policy to provide technical analysis (not just the conclusion) in PowerPoint.