Dogla Adams (of Hitchickers Guide to the Galaxy fame) has an interesting perspective on this:
"AMERICAN ATHEISTS: Mr. Adams, you have been described as a “radical Atheist.” Is this accurate?
DNA: Yes. I think I use the term radical rather loosely, just for emphasis. If you describe yourself as “Atheist,” some people will say, “Don’t you mean ‘Agnostic’?” I have to reply that I really do mean Atheist. I really do not believe that there is a god - in fact I am convinced that there is not a god (a subtle difference). I see not a shred of evidence to suggest that there is one. It’s easier to say that I am a radical Atheist, just to signal that I really mean it, have thought about it a great deal, and that it’s an opinion I hold seriously. It’s funny how many people are genuinely surprised to hear a view expressed so strongly. In England we seem to have drifted from vague wishy-washy Anglicanism to vague wishy-washy Agnosticism - both of which I think betoken a desire not to have to think about things too much.
People will then often say “But surely it’s better to remain an Agnostic just in case?” This, to me, suggests such a level of silliness and muddle that I usually edge out of the conversation rather than get sucked into it. (If it turns out that I’ve been wrong all along, and there is in fact a god, and if it further turned out that this kind of legalistic, cross-your-fingers-behind-your-back, Clintonian hair-splitting impressed him, then I think I would chose not to worship him anyway.)
Other people will ask how I can possibly claim to know? Isn’t belief-that-there-is-not-a-god as irrational, arrogant, etc., as belief-that-there-is-a-god? To which I say no for several reasons. First of all I do not believe-that-there-is-not-a-god. I don’t see what belief has got to do with it. I believe or don’t believe my four-year old daughter when she tells me that she didn’t make that mess on the floor. I believe in justice and fair play (though I don’t know exactly how we achieve them, other than by continually trying against all possible odds of success). I also believe that England should enter the European Monetary Union. I am not remotely enough of an economist to argue the issue vigorously with someone who is, but what little I do know, reinforced with a hefty dollop of gut feeling, strongly suggests to me that it’s the right course. I could very easily turn out to be wrong, and I know that. These seem to me to be legitimate uses for the word believe. As a carapace for the protection of irrational notions from legitimate questions, however, I think that the word has a lot of mischief to answer for. So, I do not believe-that-there-is-no-god. I am, however, convinced that there is no god, which is a totally different stance and takes me on to my second reason.
I don’t accept the currently fashionable assertion that any view is automatically as worthy of respect as any equal and opposite view. My view is that the moon is made of rock. If someone says to me “Well, you haven’t been there, have you? You haven’t seen it for yourself, so my view that it is made of Norwegian Beaver Cheese is equally valid” - then I can’t even be bothered to argue. There is such a thing as the burden of proof, and in the case of god, as in the case of the composition of the moon, this has shifted radically. God used to be the best explanation we’d got, and we’ve now got vastly better ones. God is no longer an explanation of anything, but has instead become something that would itself need an insurmountable amount of explaining. So I don’t think that being convinced that there is no god is as irrational or arrogant a point of view as belief that there is. I don’t think the matter calls for even-handedness at all. "
http://www.americanatheist.org/win98...silverman.html