What are emerging/promising areas of tech to get into today?

What fields in tech are going to be prevalent, disruptors or gain a foothold in business or consumer markets?

I have seen that people on forums like this one and stackoverflow are usually able to predict the next big things in tech quite well. Like this thread:

https://news.ycombinator.com/item?id=21324768&p=2

So, what CS areas would be good to invest time in learning for the near future?