Pretty much that Nan. Besides, depending on your definition of God, it might be required for one to exist. If you define 'god' as the thing that caused the universe to begin, then one definitely exist(ed), it just might not intelligent. The Big Bang would have been a deity. Or rather, whatever caused it. Even if it was just a spontaneous event caused by, say, a stray particle hitting another stray particle. It gets weird. If your definition is "intelligent being that governs the day to day, instant to instant phenomenon of the universe" then.....well, it's still possible, it just may be an incomprehensible being, and heck, one of the elementary particles might BE God. We are governed by the interactions of these particles, why can't they be this thing we call God? My point is, you cannot say that it does not exist merely because there is no evidence. And heck, something we already know about might even be it, we just don't understand it enough and semantics gets in the way (again....).
Full disclosure, although I do not like discussing my actual beliefs in this sort of medium, I am not a theist, nor am I an atheist. I hate saying I'm an agnostic, but that's about the closest to what I am. Somewhere between atheist and agnostic, kind of.