This book could have been about half the thickness (and therefore presumably considerably cheaper). It contains a great deal of repetition, as mentioned by others, but also completely pointless explanations (does anyone contemplating creating content in Joomla! really need an explanation of what 'Save' and 'Save & Close' do?).
The editing/proof-reading is poor. There are tables with headings that are not shown correctly, and grammatical errors - e.g. how exactly can I help my predecessors without the use of a TARDIS? I suspect that I may be able to offer considerably more help to my successors! How was that missed? The quality of the content is more what I would expect of something self-published on-line rather than having been checked by a proof-reader and multiple editors!
Even worse, there is advice that is plain wrong. The section on security says that PHP should have magic quotes GPC turned on. You can't install Joomla! 3 at all (without a hack which is not advised) if it is turned on, and the advice to do so directly conflicts with what is said in the section on installation. There is some useful information given but this book is not worth the money and you'll get more useful information on Joomla! (which itself I am finding to be an excellent CMS) from the Internet.
Overall, it seems that this is a very poor update of the original edition for an earlier version of Joomla! and the lack of attention to detail for the new version is very disappointing
A nicely well written book explaining all of the basic joomla functions and how the system works. The only drawback is that (due to the detailed nature of the explanations) there is quite a bit of repetition of process meaning you tend to skim through some of the sections. For a person new to the Joomla system tho it was a great introduction.