One can really feel that the author cares and is passionate about the RPG theme, so this is definitely a great book for rpg lovers. The title "RPG Programming USING XNA Game studio 3.0" is not "XNA Game studio 3.0 - RPG style!" for a good reason.
This book is NOT about setting up your 2D camera and drawing Rectangle()s. This can be clearly deduced from the page 191 where the author STARTS to implement the graphical part of the game: "The reason I've held off with graphics is partly because I'm of the opinion that graphics are one of the least important parts of an RPG."
The first almost 200 pages focus completely on building the RPG architecture for the game, having NOTHING to do with XNA. They are just C# classes, data types etc, structured in a well thought out and organized fashion.
The reason I am rating this 4/5 is because I think it shows an important concept of separating logic from graphics. There are some really nice tricks of how to do this throughout the book.
Unfortunately, the book suffers from very little detail in this respect. A lot of time is spent on describing the usual RPG terminology (like dexterity and strength) while some of the more fun XNA related bits (using sprite-batches and other XNA resources outside of the Game-class environment, making use of xna component system, reasons for structuring your project in a certain manner) are glossed over and you are directed towards code.
While reading the book I felt as if any one chapter after page 200 could be expanded into a book of it's own (which I certainly hope the author does, and which I would be glad to read!). Format similar to that of "XNA 3.0 Game Programming Recipes: A Problem-Solution Approach" would suit perfectly the authors succinct writing style.
Another downside is that a lot of the code fails to compile with game studio 3.1. While it is possible to fish out and replace references with new and updated 3.1 dlls, I feel as if the author should have made an effort into updating the source code for 3.1 release.
In conclusion, if you are an aspiring game developer, and you've poked around the XNA thing for at least a couple of month, and want to start on a solid RPG game - this book is for you. It will teach you EVERYTHING you ever wandered about how rpgs are made.