As I see it, there can be only one of two possible outcomes for our species this century: 1) our accelerated and guided evolution into a posthuman/postbiological species and a future of nearly limitless possibility, or 2) extinction (or at the very least civilizational collapse leading to the steady and inexorable regression of society and our species).
Factors in favour of 1) include the relentless onslaught of Moore's Law and the prospect of Drexlerian nanotechnology. The primary factor in favour of 2) is the steadily increasing number of existential risks that our species faces, including the threat of nuclear weapons, a disaster or war with nanotechnology and/or advanced robotics, or something involving the emergence of artificial superintelligence.
Sixty years after the advent of nuclear weapons, and at the dawn of the 21st century, we are euphoric that we have survived this long, leading us to forget that the means to our own extinction are still within our very hands. But the sad truth is that as more and more time passes, we are faced with the reality of having to live in perpetuity with a steadily increasing number of apocalyptic technologies.
Not a good prospect.