I don't think 50-100 years is enough time to say there will be a radical alteration of the current trends happening within the Religious World. Christianity will be more prevalent in 3rd World Countries, the rift between non-religious, somewhat religious, too religious will continue to grow in the US and there will still be a decline in Western Europe. India will still be mostly Hindu, Buddhists will continue to keep getting pushed to the side, and Islam will liberalise in some places, and stay just as hardcore as it is now, in other places.