I've never been good at figuring out the next big thing. Predicting human behavior doesn't seem to be one of my core competencies.
But... there is a group from Harvard that is attempting to develop a methodology for doing exactly this.
These are their first three books on the subject:
I have a copy of Seeing What's Next. I'm only about 50 pages in. It's boring academic reading. I may give it another try soon.