This is an important thread, I think.
My son is 9 and we have been doing the fade since his 8th birthday. Its amazing what he says when he realizes that there are no longer any boundaries on belief. He continually says things like- "maybe there isn't a God. There isn't really any proof." Anyone who says "Children naturally believe in God" have never spoken with children in an honest and open manner. (Ok - that was a pretty broad generalization- I expect some flaming for that) Children have a natural logic that simply can't accept much of what is taught in the Bible (especially the OT).
He has made comments like "We really dont do our religion anymore." To which I say-"No, we don't. Sometimes its important to rethink what you've always believed to be true."
To me, its important that he know that there may not be any fixed, unquestionable religious truths and that life is a journey of discovery. I'm trying to balance that with giving him a set of moral boundaries (stealing, hurting others, hurting yourself is wrong) but I find that children do have a bit of a natural compass when it comes to basic moral issues. (They just have no natural moral compass regarding stories of brutality in the OT, senseless doctrines like blood, and other artificially imposed religious "morality")