If I may make a suggestion(two, actually) when signing up for the site, it asks for your current or birth religion.
First, 'None' is not an option, which seems very strange for a site full of atheists. :)
Second, being able to separately specify current religious status and former religious status would be useful. As it is, there is no differentiation between someone who was religious and is now an atheist with someone who is still religious. Not to mention the people who may have tried 3-4 different religions before ending up at whatever their current position is.