I see religion declining in the short run but it isn't necessarily for the better as those that leave religion often pick another superstition to distract them from their mortality. Another thing to factor in is that the non-religious through their "duty" to be more considerate of the environment and the resources available on the planet, tend to have fewer children- the converse can be said of the religious. In the long run I see the religious demographic increase, unfortunately it won't be the increase in the more tolerant form of religion either.