James Lovelock, the originator (with Lynn Margulis, Carl Sagan's first wife) of the Gaia hypothesis, is now fairly certain that humanity's window of reckoning (or opportunity) to reverse course is about ten years (review of his not-yet-available-in-the-USA new book, The Revenge of Gaia). Reverse course NOW or else. And he's not talking about recycling.
Of course he is wrong! We have more time than that (because I say so!), maybe 20, 50, 100, 500 years; who knows. But it doesn't matter; to humans 10 years is the same as 200 or 50,000, a long time, and "I don't have to worry about it now." It's like owing money to the IRS; the interest and penalty payments are steep, so just live your life, and when you die the debt goes away. The only difference is that with Gaia, your quality of life suffers palpably, and your children and grandchildren will inherit your debt and may not thank you for it!
So for those among you who are really committed to a pleasant future, I'd suggest: stop talking and DO something.