If what I see from atheists on social media is any indication, it seems that most atheists are quite optimistic about the demise of religion. Many seem to think that we probably won't see anything we would recognize as religion in as little as 50 years from now. I think this would be great, but I am not nearly that optimistic. In fact, I'd probably say that we are as likely if not more likely to see a resurgence of religion within that span of time.
Yes, I have seen the same trends you have. There has indeed been some positive movement in the right direction, especially when one focuses one's attention outside the United States. And even in the United States, the numbers look good when it comes to young people. Maybe I would feel more optimistic if I was not living in Mississippi. But all it takes for me to descend into pessimism is to look at the prevalence of Christianity among our elected officials and the near-constant barrage of church-state violations taking place in every state. We have made progress, but we have such a long way to go.
Another factor contributing to my pessimism is the trends showing that we are moving in the wrong direction in some important areas. For example, belief in the paranormal is increasing in the United States. This will not surprise anyone who has flipped through the cable TV channels in the past few years. The paranormal stuff is everywhere, and it is not limited to October. I don't know about you, but I'm not terribly interested in replacing organized religion with a hodgepodge of paranormal beliefs (even if some of them are kind of cool). I feel the same way about homeopathy and assorted New Age bullshit.
Is there a relationship between the decline of organized religion and increasing belief in paranormal phenomena? Probably. It does seem like some people are determined to believe in garbage of some sort and may simply shift from one type to another. Without scientific literacy and with the profit motive being pursued by those who benefit from belief in the paranormal, it should come as little surprise that it is increasingly popular.
And it is this that forces me to once again confront the reality that most people are not terribly bright (i.e., by definition, half the population is less intelligent than average), not particularly skeptical, and do not base much of what they believe on evidence. I hope that organized religion is declining and will continue to do so, but I am not eager to see it replaced with another form of drivel. We've got to figure out how to do better than this.