The emergence of this new religious sensibility has been, as such things always are, a gradual process. Historian of religions Catherine Albanese in her useful 1990 study Nature Religion in America has traced it back in American religious life to colonial times, and its roots in older European cultures go back considerably further still. That said, it seems to me that the last few decades have seen the new religious sensibility approach something like a critical mass.In the months and years since he wrote this, I have started to see examples of this emergence in popular culture that proclaim this new sensibility with all the subtlety of a thunderclap.
The most recent, and most in-your-face example of this trend has been The 100, a TV series based (extremely loosely) on the book of the same name (and its sequels) by Kass Morgan. In this story, the survivors of a nuclear war have been living for centuries on a space station, and the story begins with their return to Earth. Earth is an uncertain and dangerous place, but the longing for the characters to return to their natural home is palpable. There is no desire for an escape from life, as is evidenced in the older religious sensibility, but a deep desire to embrace life, in all its beauty and pain.
I would recommend the books to anyone interested in examples of the new religious sensibility in pop culture. The science is a little sketchy at points, but the story is generally fairly good, at least as far as young adult fiction goes. The TV show, as I mentioned, is only loosely based on the books; unlike the books, which generally aim at a feeling of realism, the TV series features the usual dystopic tropes of zombies and vampires (both dressed up in sci-fi drag) and rogue AIs. Still, the notion of humanity escaping the human condition and going to the heavens plays no part in the TV series. (At least not yet; who knows where they might take it?)
I think it is telling that one of the strongest example of this new religious sensibility comes from young adult fiction; the abandonment of the notion of an escape from the human condition seems most advanced among younger people (even though they certainly have plenty of reasons to want to escape from the human condition, given the future our society has created for them). This fact alone seems strong evidence that Greer is on the right track about both the trend and the timing of the emergence of this new religious sensibility.
As I explore these topics related to religion and my own beliefs and practices, I should say that this new sensibility has appealed to me for a long time. When I was growing up, the only heaven that ever made any sense to me as a reward for a life well lived came in the form of a vast untrammeled wilderness with unlimited opportunities for adventure and exploration. As I reflected more on this over the years, I came to the realization of the immanence of that heaven in the real world. I am exploring, in a number of ways, how to reform and transfigure my understanding of Christianity to meet these new understandings and the demands of our current age, and it seems clear to me that this process will necessitate changing almost everything about our religion, from our understanding of the divine down to the details of our practices and rituals. It should be, at the least, quite an adventure!