What are the 'hottest' future areas of Machine Learning and Data Science? What would you guys identify as the most important areas of machine learning and data science in the future? What kind of business do you see companies focused on ML doing in the future?

To give some background to the question, I'm asking this as someone hugely interested in ML at a conceptual level but with no real experience on it save for some online courses. My intention is to learn the necessary math, coding, etc. and as I'm very entrepreneurial person, eventually found my own ML company. I've found that the field is vast and thus I feel one of the biggest challenges is to select a specific area (I guess method would be a better word here) to focus on and build expertise.
There is a brilliant answer by Yann LeCunn recently on a Quora session. 
What are some recent and potentially upcoming breakthroughs in deep learning? As he quotes, adversarial training proposed by Ian Goodfellow is one of the hottest area. Apart from that, I think Memory Networks, RNNs are widely used right now and can solve various problems up ahead.

Coming to what companies might do, I see a lot of text analytic companies. Considering the amount of consumer data we have now, there is a great need to be able to understand and analyze it. Computer Vision using ML or Deep learning is fast catching up. Using cameras for face detection, object tracking, fraud detection, tracking number plates is a huge field for companies to handle. 

Also, I think this might help you to prepare. To catch up with the overlooked developments, refer this which might give you an insight about what can develop in the future.