Having made previous posts on the notion of the Global Brain, I thought it a useful addition to make mention of another book in this area: called Metaman by Gregory Stock - UCLA academic (and, interestingly, an advocate of the transhuman society of Extropians). Metaman's thesis is that
"human society is becoming an immense living being - a global super-organism in which humans, knitted together by modern technology and communication, are playing a role akin to the individual cells in an animal's body. It presents a case that this biological interpretation of human society, which has frequently been used in the past as a metaphor, is now actually becoming a reality. This book calls this super-organism "Metaman", meaning "beyond and transcending humans". The name both acknowledges humanity's key role in the entity's formation and stresses that, though human centred, it is more than humanity alone."
Incidentally, Stock's other books include Redesigning Humans: Our Inevitable Genetic Future .