On Earth-
1) Automobile and traffic - Self driving cars (Google), cab sharing (Uber), electric cars (Tesla) would lead to an absolute change the existence of the current automobile scene.
2) Collapse of oil - As stated above, with increasingly optimized traffic and alternate energy sources, there would be no demand for oil any more.. At least not in the ridiculous way it is now. Oil sheikhs would lose their worth almost instantly.
3) Subsiding of the Middle East conflict - With crude oil out of the picture, the US will see no reason to stamp their brand of 'democracy' in the middle eastern states. Moreover, I'm pretty sure the people there would finally be too sick of all the fuckery going on there (looking at you, ISIS) and there'll be a complete overhaul, a people's revolution.. ending Islamist extremism (or at least minimizing it to a local nuisance), ending tyranny, ending injustice on women, etc. This is merely a prediction that I believe would be true within the next 50 years..Not based on any current evidence or fact. Just pure speculation.
4) Rise of Atheism (or at least liberal religious tolerance)- This may not seem obvious, but the dogmatic religious assholes are in the older age group and their demographic is slowly dwindling one death idiot at a time. Although, I do realize, there'll always be a significant percentage of each generation that inherits the baseless, illogical, selfish and hateful ideas from their predecessors, this would surely decrease over the generations.
5) Technology - Technological achievement would rise to an extremely exponential levels, more than it already is; so much so that it would pervade every mundane task of our life.
6) Rise of Aisan countries - Countries like India are showing huge potential for being a formidable presence on the globe, what with the economy looking up. The major hurdle in this scenario is the right wing governments' extremism, social issues like caste divide, women subjugation, etc. However, since I believe these problems are also on a decline, I'm willing to wager on this situation, however precarious it might seem.
In Space-
1) Economical spacefaring - With the hugely reduced costs of making and launching rockets and advents into reusable rocket technology (SpaceX),space exploration would become more economically viable.
2) Seeds of Mars colonization- No, we're still a long way off to actually live on Mars. But the initial stages that would prep the red planet for our arrival would be put in place by 50 years or so.
3)Farther reaching spacecrafts - Dawn - Ceres, Rosetta -67P/Churyumov–Gerasimenko. More. To. Come.
I have huge optimism for the human race. I have equal mistrust of some fucked up sub groups of mankind that can blow it all to smithereens. I guess I'll find out in 50 years..