A couple of years ago, Facebook gave every user an @facebook.com e-mail address. Mail sent to these addresses were sent to a user’s Facebook inbox (i.e. Messages). Users have had some complaints about how this was setup – for instance, messages from “strangers” (i.e. people you aren’t friends with on Facebook) could be difficult to find in your Messages.
According to Forbes, blogger Gervase Markham, LifeHacker, and my own testing, Facebook has made an attempt to make the @facebook.com addresses more prominent. Without asking or giving any kind of notification, they have hidden your other e-mail addresses on your Facebook profile (the ones you chose to show there) and have shown your @facebook.com address.
Some people have asked “what is the point of having your e-mail address listed on your profile.” Many people use it as a way to look up friend’s e-mail addresses to send them messages outside of Facebook, so it is useful as a white pages of sorts.
There’s the real problem – OUTSIDE of Facebook. I may be going out on a limb here, but it would seem that Facebook has realized that people use information on the profiles to contact users outside of Facebook. By changing the profile e-mail address to the @facebook.com address, they are now able to capture more information about you, if a friend were to send something to that e-mail address. That’s more information that they can use to sell ads and tailor other “content” to you.
Some, like Markham, are going so far as to equate this to a “Man in the Middle” attack, saying “Facebook silently inserted themselves into the path of formerly-direct unencrypted communications from people who want to email me.”
No matter how you look at it, it’s a jerk move to change data on every user profile and not tell them about it.
To save me typing, Lifehacker has outlined the steps for changing your profile back: