You're concentrating too much on a single specific problem instead of the concept overall. There are plenty of ways to have sane defaults for privacy that when people aren't happy about, they can then change. One of the simplest I can think of is to offload to facebook and/or G+. If they are a friend, they show as such, if they are a friend of a friend, they have a marker indicating that. If they are in one of your G+ groups (and maybe they require you be in one of theirs), then they show as such. Let companies with a vested interest in making it a useful interaction put some resources behind it.

Or maybe it's any one of a thousand other possible solutions, or capabilities. I'm really just trying to illuminate that when we are talking about something as far reaching as enhancing one of our senses with network information, and the unknown unknowns are enormous, I'm really just espousing a bit more caution before it's written off as useless, or a toy, or not worth the hype we've seen. I don't think we've seen a fraction of what's possible yet in this space.

> There are plenty of ways to have sane defaults for privacy that when people aren't happy about, they can then change.

No, there aren't. It is not possible for a system which is opt-in to get off the ground.

Do you want to purchase Google Glasses, which are opt-in (and which therefore identify 0.000001% of the people you see every day), or China Blackmarket Glasses, which are opt-out, and which not only cost 1/10th as much, they also identify 99.735% of the people you see every day, along with their birthdate, home address, cell phone, relationship status, sexual orientation and SSN? Which product will be successful?

No one is calling such things "useless". They have plenty of "uses". I'm calling them disastrous, and abusive, and privacy-invasive.

Nor is anyone saying they won't happen. They will, undoubtedly. And it will be ugly.

> No, there aren't. It is not possible for a system which is opt-in to get off the ground.

Opt-in was your assumption. Even so, that statement is trivially proven false. Facebook is opt-in by nature of needing an account. There's plenty of adoption.

> No one is calling such things "useless". They have plenty of "uses". I'm calling them disastrous, and abusive, and privacy-invasive.

Well, a statement close to calling AR useless (for these situations) farther up-thread is what started this.

I think the world will just adapt as needed to the new reality. Too easy to identify someone when in public? The public will adapt norms that make that harder. Right now we have assumed implicit anonymity, which isn't really anonymity at all in many circumstances. I'm not sure moving to a situation where people think about anonymity and how much of it they want when going about their lives, and then taking steps to try to achieve that level is entirely all bad. To be sure, it's got it's downsides, but I don't think ignoring the upsides and assuming that society will stay static while all this changes is unrealistic.