Re: Run for it
I'm a bit surprised it doesn't already exist. There are already a variety of glasses, goggles, and such that try to replace the watch entirely and do all the GPS, tracking, and everything all in one place. But that always ends up with heavy, bulky, expensive glasses that probably still don't do the things you actually want and can't connect with other hardware in any useful way. Having glasses with nothing more than a display and bluetooth/ANT+ to connect to other devices would make much more sense - don't try to reinvent or reimplement all the things that already exist, just give a convenient way to display the information.
Hell, a lot of cycle computers these days are little more than a passive screen that connects to all the sensors you've glued to various bits of your bike and body. It doesn't seem it should be that difficult to just stick that screen on a pair of glasses.