I have had this book for a month now and have only recently started using it and I must say it is extremely well written and enjoyable to read and use! You can dip in on subjects or wade your way through it. I've already picked up lots of tips to help streamline my web design and the explanation of the Spry tools is excellent especially as I'd never come across it before! Tabbed webpages a doddle, data display manipulation a godsend and so on. The book really does walk you through and doesn't assume that you know everything about the task you want to do.
Even if you know Dreamweaver well, there is sure to be something in this book you didn't know about! I fully agree that the title - The Missing Manual - is well warranted!
***Errata - have now finished the book, yes, finished all 995 pages and it stays good to the end! Buy it and use it! ***