This is a timely addendum to my last post on religion: Penn Says - What I think. Here is a link to the American Religious Identification Survey (ARIS), which most news stories I saw did not provide. Needless to say, think about it before you assume everybody believes what you do. It looks like a pretty well designed survey. Here is a BIG snippet:
Among the key findings in the 2008 survey: " So many Americans claim no religion at all (15%, up from 8% in 1990), that this category now outranks every other major U.S. religious group except Catholics and Baptists. In a nation that has long been mostly Christian, "the challenge to Christianity & does not come from other religions but from a rejection of all forms of organized religion," the report concludes.
The 2001 and 2008 surveys are replicas of the 1990 survey, and are led by the same academic research team using an identical methodology of random-digit-dialed telephone interviews (RDD) and the same unprompted, open-ended key question "What is your religion, if any?" Interviewers did not prompt or offer a suggested list of potential answers. Moreover, the self-description of respondents was not based on whether established religious bodies or institutions considered them to be members.
The "Nones" are an amalgamation of all the respondents who provided answers to our key question which identified them as having no religious identity or connection. The most common response was "None" or "No Religion." This bloc can be described as the non-religious, irreligious and anti-religious bloc. It includes anti-clerical theists, but the majority are non-theists.
These data and graphics are taken directly from the report, which you can find here.