Before today, we would've nominated Mother Jones as one of the top five places where we'd least expect to find a serious journalistic piece challenging the orthodoxy that gays are born that way.
Which is reason alone to recommend Gary Greenberg's "Gay By Choice: The Science of Sexual Identity."
The article is worthwhile for multiple reasons, really: as a summary of the history of thought on homosexuality, as a review of the present state of the research on the origins and causes of the same, as a thoughtful report on people who dissent practically from the established position that the only thing for people to do who experience same-sex attraction is to accept and embrace it as of their essence, as a challenge to dogmas of all kinds on the issue.
We won't even try to summarize, except to say that Greenberg shows that with people, things are not as simple as we try to make them. And if folks who debate the politics of this were simply as thoughtful as Greenberg, the discussion would certainly be more edifying to all.