PZ Meyers cheers on Richard Dawkins and his position that religion is a delusion and God is an imaginary friend, made up by adults not ready to face the world alone. I generally agree with PZ's attempts to clarify the concept of evolution and to fight the good fight when it comes to keeping it in the schools at all levels, but his endorsement of Dawkin's "casual contempt" strikes an off note. As both a trained scientist and a trained theologian, the tacit assumption that the question of the existence of God can be addressed by science strikes me as unwise. God's existence cannot be directly determined by any experiment. You can believe, you can not believe, you can believe I'm delusional -- but neither of us can prove a thing. Faith in God does not preclude faith in science, the two positions are in no way necessarily exclusive, though as the comments on the post make clear, they are for some people.
Is my (potential) delusion harmful in any way? Is there a need to correct it? It's not in conflict with any measurable reality, I care for my family (if you ignore the dust bunnies massing under the beds), pay taxes and hold down a job. Yes, some people who share my delusion behave in ways that are inappropriate, or hold beliefs in clear conflict with material reality. I would note that there are those who do not share in the delusion who also exhibit inappropriate behaviors and hold beliefs that are in conflict with material reality (UFO abductions anyone?). I'm not sure the common issue in all this is the delusion, but perhaps the issue lies more in the lack of respect for others.
It all reminds me of a story I once heard. A gentleman arrives in the ER, in clear need of psychiatric care. He begs the staff to let him call his agent, "I'm a world class violinist!" "Right!," they say. Next morning, sure enough, his agent calls...he is indeed a world class musician. Moral, if you're delusional about one thing (literal creationism), you may not be delusional about everything.