As the title says, this book is an excellent introduction to Direct X 10 programming.
If you are new to DirectX programming, this book is pretty much what you should start with. I have tried several others, but Frank's books seem to still be the best and this third incarnation is no different.
With this in mind, there are some necessary pre-requisites before you read this book.
First, you should have some prior knowledge in matrix algebra. Frank does dedicate a section to this, but you definitely should have taken a course prior.
Secondly, you must be familiar with basic C++ concepts. If you are unfamiliar with classes, structures and pointers this book is not for you. Get a good book on C++ programming before hand.
Finally, although it is not strictly necessary, you should have some knowledge in WIN32 programming.
This is definitely a good beginner book, and I highly recommend it.