Echoing this, mine was defaulted to off. I imagine it's correlated to another privacy setting, so for those of us who keep it fairly locked down it will likely

Echoing this, mine was defaulted to off. I imagine it's correlated to another privacy setting, so for those of us who keep it fairly locked down it will likely default off, although it's entirely possible that it's an A/B test and everyone should be sure to check the setting (Hamburger -> Account Settings -> Face Recognition Settings)