I should lightly clarify. I don't deeply care what people think the God-Machine is as long as it isn't killing chances for RP or wildly off what the core book says (not because I'm married to any of the WoD books, but because this is the common ground for all of us).
I think it is not a philosophy, a bureaucracy, anything grounded in belief. It uses these as tools, but at its core I see the God-Machine as a machine, a thing. After that it can be a gigantic interstellar AI or a planet-sized spirit that is integrated or fused to the Command Installations. I prefer the Iteration-X/60s Technophobia view for reasons already stated: Mysteries all the way down.
I do prefer that it not be responsible for the modern monotheistic religions that feature angels and demons, but for reasons that my Atheist ass cannot immediately explain, probably having to do with free will.