Google caused a stir a few days ago when it said that because of privacy concerns Google Glass will not support apps that leverage facial recognition technology – for now, at least. Users could sideload such apps onto their devices without Google’s permission, as The Guardian pointed out, but the company could opt to block such offerings through software updates.

Google’s announcement came just two weeks after Mashable published a short piece on MedRef for Glass, a demo app targeted at healthcare workers in hospitals. The app uses facial recognition technology to identify patients, enabling doctors and nurses to share and access images, voice and text notes through Google Glass.

The ability to automatically view a patient’s records is a great use-case scenario, of course, but it’s also just the tip of the iceberg. Facial recognition could enable Google Glass users to tag friends in the photos they take with the wearable gadgets, then share those pictures with those friends automatically. It might be able to help law enforcement officers and security workers to identify potential criminals. And in perhaps the most mainstream of all uses, it could serve as a virtual name tag during social occasions and business events, presenting everything from someone’s name to her employer to mutual Facebook friends.

Opting out isn’t viable

Critics have responded by claiming that Google’s move “shivs developers” of apps that leverage facial recognition technology, lowering the ceiling of the gadget’s potential. Both of those things may be true, but Google’s cautiousness is understandable considering the letter CEO Larry Page received last month from eight members of Congress. The legislators formally demanded that Google provide answers to a wide range of questions regarding privacy concerns with Google Glass, including some that specifically deal with facial recognition technology.

That technology won’t be supported in Google Glass “without having strong privacy protections in place,” the company wrote. But the questions from Congress illustrate just how difficult it will be to come up with those protections. The legislators want to know whether Glass users could use the technology to request personal information about people they’re looking at by cross-referencing images with other sources (such as Facebook), and whether a system would be created to enable people to opt out of having their personal data accessed. Such a safeguard seems nearly impossible to establish and enforce considering how much personal information is shared through online social networks.

“Awkward,” “ugly” and probably expensive

Google Glass will face plenty of other headwinds, too. While we don’t know how much they’ll cost when they become available for consumers next year, the $1,500 Google is asking for the developer model indicates they’ll be too pricey for most mainstream users. Some onlookers have complained that they’re simply too ugly to gain mass-market adoption, and a recent survey found that the vast majority of U.S. consumers find them too “socially awkward” to wear regularly. In a nutshell, Google Glass will require that we tweak our behavior when it comes to living our everyday lives – chatting with friends, driving to work, even taking the dog for a walk. And those adjustments will take some time.

Don’t get me wrong: I think Google Glass has the potential to be more disruptive in the long term than the iPad or the smartphone, and I think Google will soften its stance regarding facial recognition technology as consumers grow more comfortable with the idea. But Google Glass will be the first major entry in a very promising market that has some huge hurdles to overcome. I don’t expect it to see huge sales out of the gate next year.