Everything gives me the impression it's like they polished up the/a RHEL3 book.
But it's done a very poor way.
The fact the practises don't differ much between RHEL3 and 4, is no excuse. Using a beta version is hardly avoidable when you write a book to publish shortly after software release.
To write a book for the desktop user (lot's of GUI indeed) is a quit good idea in fact.
This 'Dummies' glitch production does not prevent me from buying others in the series.
In fact right now I'm enjoying a 'Dummies' book about SOA and it fulfills my expectation.
If there's going to be a RHEL5 book, Mr. publisher, please don't make the same/similar mistake.
If you want to know more about RHEL4, take the Negus book e.g.

Because the title doesn't cover the content I rate this book with 1 star.
For what it does content, it could earn an extra half star.

Regards,
Han Coumans
Vietnam