Google's launch of its dazzling Internet-connected eyewear, which it calls Glass, has been so understated that it's tempting to mistake this wearable computer for just another cool plaything from Silicon Valley.
I think that would be wrong. Glass - its progeny, its successors, its imitators - is a very big deal, in my view, as big as anything that has come along since the PC and the World Wide Web a generation ago.
It's not that Google's eyeglasses are more powerful than smartphones. At the moment, Glass does less, since the range and precision of instructions it recognizes are confined to what the wearer can convey through gestures, taps and limited speech.
What matters is that Glass layers a real-time Internet presence onto users' normal visual fields - onto their everyday, curbside awareness, their routine comings and goings.
Glass looks like a pair of spectacles and works like a phone; The user sees a display that's perched above the usual band of vision. That display accommodates a continuing crawl of Internet-fueled communications - text, images and sound.
Glass gets access to your world, it sees what you see. It can draw from your social networks, Internet queries, calendar, dining preferences, the bottomless resources of the Web, to furnish you with multiple levels of information and intelligence - customized for you - to inspire your choices and shape your life.
True, the technologically adept already get that via smart phones by heedlessly stroking at their tiny screens. But Glass promises a brazen and routine simultaneity of experience, an ability to interact seamlessly with the here and now without losing rich Web-enabled connectivity - just as having the radio on never meant you couldn't talk with a friend.
That's the good news. Now the rest. For starters, Glass can record and transmit pictures and sound. It is, as privacy expert Shaq Katikala puts it, "a phone in front of your eyes with a front-facing camera."
The user is already online, so there's nothing to prevent his not just filming but posting too. That means people the Glass wearer encounters can be transformed effortlessly into amusements for the eager world beyond.
Those people don't know Glass is being used as a publishing device, so unsuspecting folks - scolding a boyfriend, cussing at the umpire, picking their nose in a picturesque way - can become the next YouTube mega-star without knowing they were even auditioning.
Meanwhile, a flood of pictures and sound from thousands of Glass users surges into a database of real-time surveillance, all images susceptible to face recognition technology - though Google says it has no plans to use this. That would enable people the wearer ran across to be ID'd and tracked.
But it's not just the privacy of others that's at risk, it's the user's too. The visuals captured and posted, the places where the Glass wearer's eyes linger - they all become part of the multi-dimensional behavioral track that users create for Google and other information brokers to harvest for advertisers or for whoever else wants to know.
Some of these issues are being raised, and the Congressional Bipartisan Privacy Caucus has asked for answers: Whether face recognition software is being considered, how Google will avoid collecting data without consent, what will happen to personal information if a device is resold, what Google regards as privacy infringements.
Perhaps the most disquieting possibility is that the expectation of being watched would become the norm. As techie blogger Jared Newman wrote: ""If there's one thing we should really worry about, it's that we'll treat each other differently, and trust each other less, when Glass is around."
Or as a reviewer for Engadget put it, the situation could evolve to where "nobody knows if you're not taking a picture or video of them."
The result: That people grow more guarded, less candid, less forthcoming, worried about how strangers might regard them - and a communications miracle ends up suppressing communication.
Edward Wasserman is dean of the University of California-Berkeley Graduate School of Journalism. He wrote this column for The Miami Herald.