It is often brought up that most of the top scientists are non-theistic (i.e. they are atheists, agnostics, or believe that there may be some sort of God, but not a personal one) as proof that religion is silly and the refuge of the deluded.
The argument is essentially that science disproves the supernatural, and thus religion is entirely due to the ignorance of the masses. The fact that the top scientists are not religious proves that science and reigion are incompatible, and that science is correct and religion wrong.
What is ignored, however, is the issue of professional bias. Scientists study natural things, things that can be studied scientifically (i.e. by reproducible methods that are falsifiable). The supernatural is by its nature ascientific, that is, outside of what science can study. Belief in the supernatural is not by necessity antiscientific or unscientific, unless it makes you reject the things that science has actually found (e.g. you deny the theory of gravity). It is rather ascientific, outside of science.
The fact that so many scientists reject the existence of the supernatural is, I think, less evidence that the supernatural cannot exist than it is evidence that they have given in to professional bias; that is, they believe that anything that they cannot study through their methods cannot exist. It is hardly surprising that the top scientists tend to come to believe (or come from those who already believed) that nothing exists outside of the natural world, after all, if your tool is a hammer, everything looks like a nail.
However, we are left with a question here. Can this professional bias be found in other fields?
Of course. Most notably, it is found in economists. Some of the most brilliant economists are so in love with their field of study that they come to think that all of life can be explained in material economic terms. Issues such as culture and people's biological and cultural limitations are often cast aside as irrelevant, in the belief that a desire to maximize one's material comfort is all-important (in a certain sense, all behavior can be reduced to economics, that is, making choices as to how to use limited resources; however, when we talk about economics we are usually thinking in terms of material comforts, and most economists when trying to analyze society do so in this way). This is part of why so much of the world seems to resist the economists' theories: they are not taking into acount things that go outside of their field of study.
So what does this mean for religion and science? It does not prove that the supernatural exists, of course; that some arguments for atheism are not valid, or not entirely valid, does not make the atheists wrong; moreover, that they are not entirely valid does not, of course, mean that they are not valid at all; definitely the fact that many or most scientists are irreligious is not a neutral argument or one that would support belief in the supernatural. However, it makes those arguments less than the devastating blows to religion that some of the antireligion critics think they are. what it does mean is that "what do the top scientists believe?" is not necessarily the only or best guide for determining the possibility of the existence of the supernatural, anymore than economists should be the sole or primary guide to social policy.
That is all.