Personally I think religion will be a source of community in the coming crisis - a place where people can cooperate more instead of isolating themselves ever more. We have had End of Suburbia screenings at churches. I am doing one in December at a Unitarian Church on Staten Island.
And seeing as we're looking for a "prosperous way down" would one really want organized religion (which hasn't always been noted for its ethical and rational approach to the long view) to take action on something like this? I would prefer to see a groundswell of people from more liberal organizations take the reins, but then again, the church (catholic) is likely a better choice than the neo-cons. It seems like there's a lot of getting in bed with our enemy's enemy. While it may be necessary to raise awareness and prepare for a softer landing, I think skepticsm about ulterior/less-than-altruistic motives should be kept alive--I know I am sometimes afflicted with greed, malice and other base desires, how different can the papacy be?
You are touching on the deeper reason underlying the unsuitability of organized christianity to spread the word about Peak Oil.  Most of them (including the leaders and intellectuals) do not behave as Christians ought to.  In particular, they do not make a serious effort to find the truth and live according to it (Peak Oil being merely one example where this applies), and they do not seriously heed the Bible's stern warnings against the spiritual hazards of wealth and power.  These historically endemic realities go a long way towards explaining organized Christianity's failure with regard to Peak Oil.
As it happens, the article that just appeared today at the following link gives a very apt illustration of WHY wealth and power are so spiritually dangerous:

http://www.counterpunch.com/jensen10052005.html