I enjoyed this book very much, although I'm still not sure if Gaia is alive. Gaia exhibits local entropy reduction which is a character of life, but so does the galaxy with star formation in the spiral arms. The book is thought provoking and has been updated well in this edition, although the importance of chaos theory to support the Gaia theory is not adequately explored. Deep Simplicity Deep Simplicity: Chaos, Complexity and the Emergence of Life (Penguin Press Science)
expanded on this and I would recommend it.