The book is exactly what its title says, a source of information and code that make using microformats dead simple to use and easy to understand--all wrapped up in the logic of semantic HTML and web standards.
If you care at all about semantic HTML, SEO, accessible data, reusable content, or web design you need to read this book. I suggest you read the book sitting by your computer, because you are going to want to implement microformats as you read through the chapters. It's so easy and the benefits are so clear, you can't read the book and not want to use the information. In many cases you can add microformat data instantly as you see the code examples provided and apply the concepts to your own sites.
If you are teaching HTML or any beginning level web development class, you could add microformats to your course with almost no effort by adding various microformats at appropriate moments as students learn new material. This book would guide you in that effort. If you are a student of HTML who wants to improve your website with microformats, this book will take you there.
This is a terrific book.