I read the version 2.0 of this book, which was revised by Richard Stallman himself.
The book is amazing. I'm not a fan of biographies or auto-biographies, but most of this concentrates less on Stallman's emotions and thought processes as it does on the notable events throughout the development of GNU, the FSF, and, eventually, the projects that were so greatly influenced by the very presence of GNU.
EVERYTHING technical was interesting. Actually, it was riveting. Reading about the hacker culture within MIT during the 70s, and the rise of locked-down software and the struggle to keep code free, the stories about how rms developed GNU Emacs, and GCC, and GDB, and how the GNU team developed glibc and make and so many other hugely important software innovations, the ramifications of which we are still benefiting from today, was absolutely enthralling. On one hand, it saddens me that things have turned out so muddled and proprietary in spite of these valiant efforts, and on the other hand it strengthens my resolve to continue fighting for programming liberty and transparency.
You can pretty much skip the Preface and Afterword. Otherwise, most of this book is great. The author's personal reflections upon rms are not as interesting to me; personal observations are neither here nor there. The real star of this book is the [free] hacker ethic, software liberty, and the GPL.
Which reminds me: the book is published under the terms of the GNU Free Documentation license (presumably because Creative Commons didn't exist at the time of publication). Pretty cool.