This op-ed by Charles Blow tries to explain increases in American tolerance of gays and lesbians (even perhaps homosexuals).
For the first time, men may actually be more tolerant than women of "gay and lesbian relations."
Why? More people now know someone who is out of the closet (we always knew gays and lesbians, we just didn't know their orientation). The second explanation is a bit more surprising--that men have become more tolerant in general of "others." This would not seem to be reflected in the rhetoric of certain parties, but the reality of diversity (that it is actually not a bad thing) may have penetrated attitudes. Third, well, "Virulent homophobes are increasingly being exposed for engaging in homosexuality."
I would vote for the first two more than the third, especially the second. That is, political correctness in the best sense of it is that it is no longer ok to say that you hate or are intolerant of a class of people. Lots of people are critical of PC and rightly so when it means knee jerk reactions that close off debate. BUT over the past twenty or thirty years, it has become relatively unacceptable to say racist, misogynist, and even now homophobic slurs in public. This does not mean that racism, sexism and homophobia no longer exist (sorry, Stephen Colbert), but that the social costs of uttering such slurs have gone up. It is just no longer seen as taken for granted that one can diminish others unless one is very certain that the people hearing the slur are all like-minded. And that is less likely than it once was.
With all of the anti-immigration anxiety, all of the Tea Party demagoguery, all of the Obama backlash, it is nice to know that there are some broader, perhaps more enduring trends, about attitudes that are more tolerant. And if it is driven by homophobes being driven out of the closet themselves, then that is pretty cool, too.