I'm always amused by arguments about whether or not there is some sort of omnipotent being out there.
Yup I am agnostic. There is absolutely no way to prove either for or against the existence of an all-knowing, all-powerful deity without the direct intervention of said deity in a very clear and direct way.
1) Argument against the Atheist religion. It IS a religion, the only difference being that they believe there's nothing there, and can't prove it.
If there is an omnipotent, omnicient being out there, it's more than capable of hiding itself from us. Even if there is evidence of it's existence, it could erase said knowledge from our minds, or make us incapable of seeing or properly interpreting the data to begin with, because it knows everything we do, and has the power to do anything, and the knowledge to use that power. You cannot disprove the existence of such a being. You can have faith that there is no deity keeping itself hidden from us, but you cannot know it.
2) Argument against the Theist religions.
For so long as a potential deity does not choose to prove it's own existence conclusively, the only evidence supporting it is circumstantial at best. If an omnicient, omnipotent being chooses to make itself known, it can most certainly do so, so the fact that it is NOT proving itself to exist means that either it does not exist or it does not want to be conslusively known to exist. You can can have faith, but you cannot prove or speak with factual certainty.
It is conceivable that an omnipotent, omnicient being would not WANT us to know for certain that it exists, and it might be actively concealing itself from us. There is a big difference conceptually between having faith and having certain knowledge. Even on a personal level, how often are our expectations of a person different when we know them only by reputation as opposed to when we know them as a friend or colleague? It might be that a deity would prefer to have some portion of humanity believing in it, rather than all of humanity knowing it exists. If said deity was known to exist, the relationship between it and humans would have a completely different aspect. For all anyone knows, if such a being exists, it might actually draw sustenance or pleasure from worship. Or maybe it would rather hear a few hundred million prayers per day, as opposed to billions of self-serving demands. It seems unlikely to me that a deity would be masochistic.
In essence, there is not even a possibility of humans either proving OR disproving the existence of a deity. The fact that humans cannot possibly generate such a proof is based on the nature of an all-powerful, all-knowing deity. With that power and that knowledge, we will only know for certain if it exists if it chooses of it's own volition to verify it's own existence, and we can never know for certain that it does not exist.