I’ve come across quite a number of articles recently which suggest, essentially, that belief in the active presence of God in the world is a trick we pull on ourselves which served, at some point, an evolutionary function. Here’s a little round-up:
The Atlantic Monthly:

Despite the vast number of religions, nearly everyone in the world believes in the same things: the existence of a soul, an afterlife, miracles, and the divine creation of the universe. Recently psychologists doing research on the minds of infants have discovered two related facts that may account for this phenomenon. One: human beings come into the world with a predisposition to believe in supernatural phenomena. And two: this predisposition is an incidental by-product of cognitive functioning gone awry. Which leads to the question…

Is God an accident? (Subscription required. Full-text removed at request of The Atlantic.)
A new documentary on BBC4 called Jonathan Miller’s Brief History of Disbelief examines the culture of atheism. Check out his interview with Pascal Boyer.
In Edge, Daniel Gilbert writes,

Is God is nothing more than an attempt to explain order and good fortune by those who do not understand the mathematics of chance, the principles of self-organizing systems, or the psychology of the human mind? When the study I just described was accepted for publication, I recall asking one of my collaborators, who is a deeply religious man, how he felt about having demonstrated that people can misattribute the products of their own minds to powerful external agents. He said, “I feel fine. After all, God doesn’t want us to confuse our miracles with his.”
That’s fair enough. Science rules out the most cartoonish versions of God by debunking specific claims about ancient civilizations in North America or the creatio ex nihilo of human life. But it cannot tell us whether there is a force or entity or idea beyond our ken that deserves to be known as God. What we can say is that the universe is a complex place, that events within it often seem to turn out for the best, and that neither of these facts requires an explanation beyond our own skins.

The Vagaries of Religious Experience
Finally, a more thorough round-up at 3quarksdaily, in which Abbas Raza asks, “Until recently, few scientists have put much effort into explaining the ubiquity of religious beliefs. If it is so irrational, then why is religious conviction so widespread?”