I think the decline in church attendance has a lot to do with not being able to square spiritual knowledge with scientific/factual knowledge.  People get caught up in trying to prove/disprove whether a particular event in the bible happened.  Religion tells truth the way poetry tells truth.  But of course if you're going to insist on yes/no fact instead of spiritual truth then you're left with either abandoning religion entirely, or adopting biblical literalism.  I happen to belong to one of the declining liberal denominations the author mentions.  I find it provides a lot of meaning, solace, connection to a wider community, and intellectual stimulation.  I'm sad to see the numbers in more liberal churches dwindling, but the conservative and literalist churches are completely unappealing.  I think they're trying to harken back to a time that never was.  They say much more about our current age than what faith was about in centuries past.