I was a bit disappointed in this book. It seemed quite basic and a lot of the information in could have been figured out by reading the jenkins website or a tutorial.
I've used jenkins a little bit and there are 2 things that I find very frustrating with it. I'm going to outline these 2 things to show the sort of solutions that I was hoping to find in this book, but which I did not find. My first jenkins problem is that if I run jobs A, B, or C in series, all 3 succeed. However, if I run jobs A, B, and C in parallel, several of them randomly fail. My jobs A, B, and C do not interact (i.e. they update server A1, B1, and C1), so I would think that they could run simultaneously. So far, our best theory is that our jenkins server does not have enough ram or cpu or something, but I would expect a better message from jenkins like 'out of memory error'.
My second problem with jenkins is that I find it very hard to figure out why a job fails. When I go to the logs, there are sub-jobs containing sub-jobs containing more sub-jobs and I'll have to check 5-10 different log files to figure out which one failed and why.
One of my goals from reading this book was to learn something that might address my two frustrations with jenkins, but instead I get really basic stuff like how to download java 6. Or information about a project called Hudson (which I'm not interested in). So I suppose that I'll need to spend some time on stackoverflow or google to try to figure out jenkins instead of finding answers in this book.
Note - the book is well written and easily readable if you have no jenkins experience. It is just not well suited for intermediate/advanced users.