I believe they will fade away or evolved into more of a VR device (gaming). I have glasses but they are not something I enjoy wearing. I buy glasses that are aesthetically pleasing and I cannot imagine a tech company being able to design something that is somewhat fashionable. I personally feel some things should be unconnected, every day glasses being one of them. I love tech, but my smartphone is all I really need connected. However, if x-ray vision comes to glasses, I'd buy a pair. :)
They won't probably be glasses, but rather some sort of implant to your eye. That's pretty far off though, and I would like to get something like Google Glass, just higher resolution (and battery capacity).
I think as nanotechnology gets better over the next decade and we start seeing fabs that can push out architectures at under 7nm, a lot of implant and contact lenses will finally have a chance to shine. The constraint right now is providing power to small devices on the molercular level as as well as having enough processing power to do things. If you can get a contact lense that is powered through the light in the room or thermal energy from the body, combined with a sub 7nm chip, we'll definitely start seeing some amazing gadgets.