The first thing I have to say about this book is that it is very detail oriented. It truly is a beginners guide. I'm positive I could give this book to my father and he'd be able to install, configure and run VirtualBox on Windows or Linux. It outlines, in step-by-step detail, everything you'd like to know about VirtualBox. Even though I consider myself a Virtualbox veteran, I followed along with some of the tutorials and was impressed that no detail was left out.
One of the things that really stands out about this title is that it includes a huge number of screenshots. The number of screenshots in the book provide any beginner with the visual roadmap they need to complete the task at hand. It covers installing VirtualBox on both a Windows and Ubuntu host, as well as installing and configuring the reverse as guests. If you've never installed VirtualBox before, you'll have an installation up and running in just a few minutes.
Beyond installation and configuration, this book goes into detail regarding the command line options (I learned quite a bit from this chapter!) as well. VirtualBox provides a full set of command line tools for starting, stopping, configuring, cloning and creating virtual machines. This makes it a perfectly reasonable candidate for a headless server virtualization solution!
This book covers guest additions, disk and image creation and management, all networking options and how they differ, using and creating virtual appliances, using snapshots and even remote management. It really is a good resource for getting started with Virtualization. I'm glad to have a copy of this book in my collection.
The sections that were the most useful for me were the networking and command line chapters. I was not familiar with any of the command line tools, and the networking was a little blurry for me. Before getting a copy of this book I was unfamiliar with virtualized networking beyond NAT and Bridged. This book went into enough networking detail that I'm very comfortable with each of the networking options and in what situations each might apply. This will really boost my efficiency and productivity with VirtualBox.
For anyone wanting to learn more about virtualization or doing research into cost-effective virtual environment solutions, I would highly recommend VirtualBox 3.1 Beginner's Guide.