This book offers a good guide to creating an online WordPress community from scratch. Among the topics covered are descriptions of WordPress MU and BuddyPress, installing it, increasing traffic to it and what to do when things go wrong. I felt the step by step directions explained various topics well. Of course WordPress is very dynamic and changes versions often. Consequently, some screens shown in the book may appear differently when you first try to set up a multi-user blog.
While this book is a book for novice users, the author assumes you already know something about WordPress. BuddyPress contains plugins that help set up your multi user blog and customize it to suit your needs. One point the author makes here that's good to remember, which is to plan your site before building it. Building a MY site requires setting up a database and server which is explained in some detail. Another chapter touches on letting your users manage their own blogs, with suggestions on avoiding issues and setting up different levels of priveleges for your users. Spam is always an issue for any blogger and the author offers some tips to make it harder for spammers to "invade" your site (making it invite-only or moderating site registration).
There's also information about adding forums, social networking and optimizing your site. All in all, I felt this book contains some good information, some that may be similar to other blogs but important information nonetheless. It's well worth getting if you're thinking about building a multi-user blog.