When Facebook revealed last year it was introducing facial recognition technology to help users tag their friends in photographs, they gave the functionality to North American users only.
Most of the rest of us found the option in our privacy settings was "not yet available", which meant we could neither enable or disable it. We simply had to wait until Facebook decided to roll it out to our account.
Well, now might be a good time to check your Facebook privacy settings as many Facebook users are reporting that the site has enabled the option in the last few days without giving users any notice.
There are billions of photographs on Facebook's servers. As your Facebook friends upload their albums, Facebook will try to determine if any of the pictures look like you. And if they find what they believe to be a match, they may well urge one of your Facebook friends to tag it with your name.
The tagging is still done by your friends, not by Facebook, but rather creepily Facebook is now pushing your friends to go ahead and tag you.
Remember, Facebook does not give you any right to pre-approve tags. Instead the onus is on you to untag yourself in any photo a friend has tagged you in. After the fact.
If this is something you're uncomfortable with, disable "Suggest photos of me to friends" now.
Here's how you do it.
* Go to your Facebook account's privacy settings.
* Click on "Customise settings".
* Under "Things others share" you should see an option titled "Suggest photos of me to friends. When photos look like me, suggest my name".
* Unfortunately at this point you can't tell whether Facebook has enabled the setting or not, you have to dig deeper..
* Click on "Edit settings".
* If Facebook has enabled auto-suggestion of photo tags you will find the option says "Enabled".
* Change it to "Disabled" if you don't want Facebook to work that way.
* Press "OK".
Earlier this year, Sophos wrote an open letter to Facebook. Amongst other things, we asked for "privacy by default" - meaning that there should be no more sharing of information without users' express agreement (OPT-IN).
Unfortunately, once again, Facebook seems to be sharing personal information by default. Many people feel distinctly uncomfortable about a site like Facebook learning what they look like, and using that information without their permission.
Most Facebook users still don't know how to set their privacy options safely, finding the whole system confusing. It's even harder though to keep control when Facebook changes the settings without your knowledge.
The onus should not be on Facebook users having to "opt-out" of the facial recognition feature, but instead on users having to "opt-in".
Yet again, it feels like Facebook is eroding the online privacy of its users by stealth.
If you are on Facebook and want to keep yourself informed about the latest news from the world of internet security and privacy you could do a lot worse than join the Sophos Facebook page where we regularly discuss these issues and best practice.
You should also take some time to read our step-by-step advice on how best to configure your Facebook privacy settings.Follow @NakedSecurity