Large numbers of people now leaving churches nonetheless continue to believe in a god. This article in the L.A. Times indicates that the marriage of conservative politics and religion is driving them away from church:

The most rapidly growing religious category today is composed of those Americans who say they have no religious affiliation. While middle-aged and older Americans continue to embrace organized religion, rapidly increasing numbers of young people are rejecting it. As recently as 1990, all but 7% of Americans claimed a religious affiliation, a figure that had held constant for decades. Today, 17% of Americans say they have no religion, and these new "nones" are very heavily concentrated among Americans who have come of age since 1990. Between 25% and 30% of twentysomethings today say they have no religious affiliation — roughly four times higher than in any previous generation.

The NYT reports on the recent Los Angeles conference sponsored by the Council for Secular Humanism:

The conference came on the heels of a change in leadership at the council and a rumored rift there, which some described as a standoff between atheists, who focus on God’s nonexistence, and humanists, who are also nonbelievers but seek an alternative ethical system, one that does not depend on any deity. Some of the weekend’s speakers alluded to the turmoil at the council, where several longtime employees have resigned or been laid off. But in general they emphasized unity: They shared common enemies, like religious fundamentalism and “Intelligent Design.” And they believed morality was possible without God.