I think this is more of a reflection of the current state of religion in the country and its move to the extremes rather than a change in people's beliefs.
Religion has become so occupied in polarizing issues (e.g. politics) and scandals, that belonging to one of these organization's has changed from being part of a philosophy/community to an extremist organization.
Don't get me wrong I'm a strong contingent of the 20% but I believe there is a place for religion as well. I believe that religion has both the ability to be productive for a community as well as very destructive for an individual.
The founders got it right with the first amendment and the separation of church and state. It's too bad that the same people who clutch the constitution so firmly in one hand also carry the bible in the other these days.