Spotted: Sergey Brin wearing Google Glass specs as he blends in on NYC subway

"That a man as fabulously wealthy as Brin uses the train to get around is quite amusing. With his winter hat, beard and plastic bag, he looks just like a regular guy."

Seems like he simply realizes that being wealthy does not mean you have to show it off at every moment by going for expensive modes of transport over actually useful ones just because he can.

It looks like a planned Google Glass marketing campaign. Why do I say that? Nobody in the picture has a phone out to detract from the Glass, when have you been on a train with people sitting down not on their phone?

Not a knock at Sergey or Google, I think its a cool depiction of what they expect the future to look like - something between seeing people everywhere wearing earbuds or on their phone except in the future people are wearing Glass.

While marketing/buzz might be one of the motivations, another factor could simply be Brin wanting a first-hand look at what every day, quick to quip, New Yorkers think of his new accoutrement. This research might be something he could delegate to others, but I respect that he doesn't.

I don't understand why Google keeps going on about these glasses when their only purpose is as an always-on video camera. Why not keep it quiet until it can do what it is supposed to do.

Because an always-on video camera is a pretty dangerous thing. Not only will you be routinely violating Civil Rights and Privacy laws but you open yourself up to assault by other people. Not to mention vigorous enforcement by the police.