Gregg,
I'd say that most of the book is "in action". I'm a practical guy, and I've been a developer and managed developers, so I know that it's more important to see how to do something than to know every detail of the API. The trick in a book is to balance between the two, and I definitely focus more on examples. There are two chapters that cover the API, and two introductory chapters that explain what
JSF is, its core concepts, and how it works. Everything else is about how to use different pieces of JSF, how to build an application, and how to build custom components. There's also an extensive case study.
Hope this helps
.