If you are familiar with R and with Bayesian Computation this book may be a good introduction to using R packages for Bayesian Computation, but I didn't feel it is a good introduction to Bayesian Computation or to R if you are unfamiliar with either or both.
This extensive (over 200 pages) book is intended to assist the use of the R programming language for Bayesian statistical calculations. It takes a step-by-step approach, using straightforward practical examples immediately. It introduces built-in R functions appropriate to each specific example and reviews them briefly at the end of each one. It starts with some simple standard descriptive statistical examples and includes useful graphical R plotting functions to display helpful diagrams. It assumes you have intermediate statistical knowledge and can move beyond the simple descriptive stats work with relative ease. It then uses these concepts to introduce Bayesian statistics after a very short introduction. In effect, you should already be aware of the principles of the Bayesian approach (initial belief modelled via prior distributions, these modified through measurements expressed in posterior distributions which are then used to draw inferences). I had some of this knowledge, but swiftly realised I would need to devote serious study to grasp it thoroughly. This is an excellent book, with an extensive bibliography, to help you along the way.
First two chapters are easy to follow, after that its down-hill. A lot of equations are stated without an explanation, no clear expositions. Writer falls into the trap of writing a book for himself and not the student. Nothing is explained clearly. No one in the 'real' world uses R, only mathematics departments in Universities, so you want be applying these functions in work related environments. No answers given to chapter questions. The book is called 'Bayesian computation in R', only if you understand Bayesian computation very well and need to see some examples in R. Otherwise your not going to learn Bayesian stats with this book.