@Anand, I do wonder, too, if Google Glass would become a tough competition for GoPro. But then, I think Google Glass tries to do way too much, and yet, it doesn't give users enough flexibility ---like putting the camera on a handle or any other part of the extreme sports equipment... I think Google Glass is another case of devices that try to do way too much and yet lack flexibility to meet specific individula usage or demand.
Similarly in a wearable device the functionality should be at the forefront and the phone capability or any kind communications capability should be a background function and should be automatically happening wihout user intervention.
Voila. I think that pretty much sums up wearable requirements.
As I watch this new industry unfold, there are many gimmics (like the dick tracy watches). However, the stuff like the GoPro camera systems are likely going to continue. It provides a way of sharing types of physical experiences that up to now (like skydiving) you either had to have VERY expensive equipment or you had to do it yourself.
I suspect many other products will just be a fad. I"m not willing to trade my VERY reliable stainless wrist watch for a gadget that likely will fail just before i need to catch a plane. Again, its the right tool for the right application.
Products that try to do EVERYTHING in a small package are likely a compromise and will have very poor reliability. Alas, there will be a market for that for the generations that don't mind buying the same device every two years.
There's no question that the GoPro is a wearable device. It's primary customer base are action sports enthusiasts who attach it to a helmet, or to handlebars, or to a pole that can be extended in front of the user to enable "selfies", as in the photo that appears in this article.
I also find it interesting that with the increasing popularity of affordable quadri-copter drones, GoPro seems to be the camera of choice for consumer aerial videography. This is a whole new and probably unexpected market for GoPro. Perhaps small now, but possibly significant in a few more years.
I also agree with the comment that Flip could've been a GoPro competitor if they hadn't been bought & buried before they got a chance to really hit their stride.