Google Glass doesn't much appeal to me. I mean I already wear contacts and glasses and really have no desire to add more eyewear. I also personally would think it would be distracting and for lack of a better phrase, to "in your face". Now admittedly I have not tried the product, that is just my perception.
As far as the rumored and much talked about iWatch, that at first didn't seem like something I thought would catch on either. However, after reading Business Insiders latest piece on it, I am seeing the potential. Latest rumors say Apple has hired "Blood Experts" to assist in development. It appears as though there is the possibility of utilizing the iWatch for medical assistance for people with diabetes, kidney illness, etc. Now in those cases, I can see the potential selling point of the iWatch vs using it in lieu of your smartphone or tablet.
I suppose Google Glass could have options up their sleeve to assist with eye conditions down the road, thus making it medically appealing. If these items had other uses other than surfing the net I think they would gain more traction. Imagine if one of these devices worked in conjunction with an app that could communicate real-time results with your doctor to assist in monitoring your health? That would be a whole different realm of possibility.
Healthcare and advanced technology have long been partners in advancements, so the possibility of coupling wearable technology with health management isn't totally out there, and probably exists already in some arena. Functionality that assisted individuals with living longer, healthier, more productive lives by assisting them in managing illness would be a huge selling point.
I know these items are still in early stages, iWatch isn't even a reality yet. But, as with modern technology, the possibilities are endless. It just goes to show if someone can dream it, technology can assist in making it a reality. Another sign that technology is our friend and shouldn't be shied away from.