Wearing "google glasses" might not make a whole lot of difference. It presupposes that the images and sounds captured by the camera will have enough fidelity to capture the details which actually matter and that's not a given even under ideal circumstances. Finally although a murder case would certainly get scrutiny, it would be hard to get a cop to even watch a video of a run-of-the-mill crime. Cyclists have been wearing video cams for years and there have been very very few cases of action being taken against motorists even when the cameras capture egregious behavior. There is no reason to think that a different maginalized group such as young black males will fare better because of google glass.
Trayvon Martin would have never turned his glasses on, you don't record yourself pummeling someone unless you want to get arrested.
You could kind of do this with a phone. Hit an emergency button and it starts discretely recording audio remotely. It wouldn't be overt, but you'd get a lot of evidence.
I'd rather be wearing an Iron Man suit that works and open a can of Whoop-Ass on 'em myself.
The question is: what is the MVP?
It would just give the defense even more evidence. The decision was about whether or not Zimmerman shot him in self-defense, NOT whether or not Zimmerman was responsible for creating the situation that resulted in Trayvon Martin being shot.
Isn't wearing Google Glasses reason enough to get shot?
This is rather disconnected from the established facts of the case.
I'll just point out the most obvious one that is totally indisputable: about the same time Trayvon might have started the suggested process that would include calling 911, Zimmerman called the police on their non-emergency number (NEN) and got them dispatched to the location.