Rating: 

I liked the short, terse CodeNotes reference that I bought, but the other 2 ... Man, half the time I didn't really understand what I was reading, and I have never seen so many errors in my life! Honestly, I didn't know if it was because the server-side was so confusing or if the authors and publishers (none were O'Reilly) just didn't care.

Then I bought this book and I am once again a happy camper. Both the text and examples are clear, concise, useful, and error-free. I really like the way the author not only explains concepts, but tells me why it is important that I know them.