Ko Ko,
I can't really speak for Hans' book, but I can tell you want I think makes my book distinctive.
(1) A comprehensive case study. Parts 2 and 3 of the book focus on building a real application, examining everything from prototyping to custom authentication,
JDBC integration, and so on.
(2) Coverage of tools. Throughout the book, I explain how different features work inside of tools, and show screen shots of Oracle JDeveloper, IBM WebSphere Studio, and Sun
Java Studio Creator. There's also an entire appendix that shows how to build part of the case study in each tool.
(3) Extensive examples of custom components. I spend a total of six chapters talking about writing custom components, renderers, validators, and converters.
Also, in addition to around 740 pages in print, there will be another 330 or so available on-line.
So, naturally, I recommend
JSF in Action. I'm probably a litle biased, though

.