This book is required reading for anyone who wants the title of web design guru.
Mr. Cranford-Teague has taken the trouble to explain both the documented use and the real-world implementation of CSS. He has taken away much of the testing that is often required when designing against the CSS2 specification. (He makes mistakes so you don't have to!) His quick reference appendix of what-style-elements-work-where should be the most heavily thumbed pages of any book in your HTML design library.
The book is small, and cheap enough to keep up with the latest browser platforms. I own all three versions, and so do all my associate developers!