Ars Technica reports on a meta-analysis of over 60 studies over the last 90 years or so that have some bearing on the relationship between intelligence (measured traditionally) and religious belief in American Protestants (and to a lesser degree in the UK and Canada, again among Protestants). They find that as intelligence increases, so does non-conformity (known from other studies); a sense of control over one's life; self-regulation (that is, the ability to defer gratification to reach a greater goal); self-enhancement (including social success and better self-image) and a higher likelihood of setting up and maintaining a long-term relationship. Thus, intelligence seems to provide people with many of the same benefits as religious belief, and so the *correlation* suggests that more research could be directed at these aspects of both intelligence and religious belief effects.
It's not a long article, and it's not unbalanced Richard Dawkins mud-slinging. Take a look before flaming.