GoPros are a fad or niche market, only because they market it that way. Even if you're not doing anything "extreme" it's really nice to have a running video of even the most mundane canoeing trip just to get still pictures and laugh at those people who kept flipping their canoe. It's the least interrupting way to record an event.

I'm surprised GoPro hasn't formed partnerships for success in other markets. High school sports, and even younger, are often filming competitions and performing automated or manual analysis to rank players and provide feedback. Schools and Boosters are paying crazy amounts of money for these services, but it could be so much better aggregating videos of ~10 mounted GoPros together to get "on the field" perspectives. Then there's the whole professional sports media market. People LOVE hearing audio from NFL quarterbacks, imagine a first person view.