Oddly, I found the most interesting material in the book to be the chapter on Jungian Types. But there's plenty of good Human Interface Design material here as well. It's fairly 90's Mac-centric in the main, and many of the examples not directly applicable to the kind of thing I'm working on right now, but the basic insights are the same. This book also prompted me to finally check out Ashlar Vellum, which turns out to be the drawing program that I've been looking for for years.