There's nothing confounding about glass that makes it LESS of a surveillance device than a smart phone, certainly there's plenty that makes it more so. What do you find accurate about the argument?
How much time do you spend being recorded naked on a smart phone in your bedroom? None I bet. I can envisage google glass, or 'google contacts' resulting in everything being recorded if you extrapolate, with no expectation of privacy.
Already in technology companies, employees may be asked to leave their phones outside, will those companies be more keen or less keen to have 'google glass' left behind? More, I would bet.
You and I both know that a camera is different to ubiquitous cameras, and that when and where those cameras are directed and recording are important. Most important of all given those first two distinctions, is who controls and owns the footage. The implications of the footage ending up on a computer not belonging to the recorder and recorded are profound. How will the law react? Mandatory recording for the typically sensitive professions? Will that then extend out in all directions? Will Joe Public be charged with destroying evidence: e.g. shop owners being sued for compensation, who destroy their CCTV footage to cover up?
The desktop computer from a "processing or data access" standpoint was not very different from the mainframes or minicomputers at the time--indeed probably much stunted!--but the changes it caused were massive outside of that limited scope.
The common argument of "Google Glass is no different a surveillance device than a modern smart phone" is so troublesome precisely because it is accurate without having explanatory power--there are confounding features to Glass that go beyond that simple comparison.