As many cookbook style, the book can only go to certain length with each example on explanation and teaching, but readers may dig much deeper by using the sample code provided by this book. In fact I think it's really cool that it's available through GitHub as well. Check it out at http://github.com/CamelCookbook/camel-cookbook-examples. (although I think there is a typo in the book for this URL on the copy I have! ^_^) The sample code are complete, clean and easy to follow for each recipe example. The source code is in Maven based project, so you will get all the dependencies needed by just running the "install" phase. Open by any major IDE and you will start reading and compiling immediately. Because it's using Maven, you can also download the Camel dependencies with Source, and you can jump right into the framework code itself to analyze what's behind this cool project.
Because it's a cookbook, it does not go into too deep about Camel internal. But through the examples, many of the core concepts of Camel has been touched; and it serves as a great example and can be used as handy reference book. Because it covers the Camel concept briefly, it expected you to know little bit of the integration knowledge and background though. Things like Enterprise Integration Patterns and transport technologies used such as File, FTP, SEDA, JMS etc. The book also comes with many Spring based XML configuration examples, and it expects you to know some basic knowledge of bean configuration. But the xml configuration of Camel routes itself are very self explanatory, so readers should able to follow along easily.
If you work with Camel project, or have to start an integration project, I would recommend you to check out this book.