"lengthy time-to-market and lack of a key consumer use case"
No.
The reason they have flopped is because no one wants to give google/facebook/the nsa all their videos and photos and everything they ever do...
...also call me skeptical, but I'll wait a few decades for the long-term eye damage assesments to be made. Or are google going to pay my medical bills in the future when one of my eyes focuses constantly on something nearby and the other doesn't...
*joke*
Not to mention the phosphor burn-in on my right eye of the google logo that now overlaps everything I see, with or without glasses.
*/joke*