This is not a book for beginners. You should know HTML and CSS (and some basic PHP) and be comfortable with editing files.
I’ve used the loop before for custom queries, but I found the way he explained it easier to comprehend than other explanations I’ve read.
I felt like some of the code displayed in the book was unnecessary, especially most of the CSS. There were a few things I would have liked to see the code for that weren’t shown, mainly in the second half of the book.
I would have loved to see the Uncommon WordPress Usage chapter expanded, with more examples and code.
It’s too bad that the book came out before 3.0 and custom post types and menus. It just came out in February, so it is pretty up to date but WordPress evolves so fast.
There were some complaints on amazon.com about the layout and design of the book but I have an issues reading it.
I did learn a few new things from the book, but mostly I found it inspiring.
I didn’t see any website listed in the book to download the code, but I did find it via Google. You can download the Smashing WordPress code from the author’s website. The only issue is that problems noted in the comments there has not been fixed yet (the question marks are replaced with a different character). But search and replace is still faster than retyping it all.
A lot of the code is taken from his theme, Notes Blog Core. I like that he uses his theme as an example, rather than making up a fake theme. It makes everything more real.
I would highly recommend this book.