I found it very much worth buying the new MMM edition for his revisiting the "plan to throw one away, because you will" discussion on prototyping (e.g. see Joel's discussion on this). Very useful to me since I'd by then experienced most of the possible outcomes of this question.

He's not one to rest on his laurels and is to be commended for turning an epic disaster into a lifetime of suggesting to us with style and verve how we might manage to avoid such ourselves.