100 years from now
Most respected scientists start to openly reject the religious premises.
Students worldwide are heavily influenced by that.
The number of open atheist politicians increase.
Elders wonder what went wrong with society, but there's no going back.
150 years from now
Religion starts to be openly associated with a low IQ, making young people much less likely to become religious. US is now 50% atheist.
Extremist muslims are diminished, as the bright young generation rejects the idea of a heaven with 72 virgins as a reward for killing people.
200 years from now
Religious people start to get bullied.
This situation is now reversed, and the hardcore atheists, now a pretty strong group, blame religion for every problem in the world.
300 years from now
Religious people only exist in isolated communities, as society no longer takes openly religious people seriously.
400 years from now
Civilized world is entirely atheist.
Current generation doesn't have a theist x atheist dichotomy (it's a no-brainer, as clear as the fact that the world is not plan), and their books portray our society as being a bit less primitive than pre-Columbian civilizations (keep in mind that 400 years of technology advancing at the current pace would make us look pre historical).
500 years from now
No one talks about religion, except in History classes. Current generation doesn't view religion as a taboo, so people don't have an automatic rejection to the idea.
Many people start developing a healthy curiosity about religion.
Then, out of the blue, an eloquent ENFJ starts selling the idea that being religious is the new cool. The speech "Our society is corrupted because people no longer believe in God" sounds innovative, and people buy into it.
And the cycle repeats.