The changed was discovered Saturday, and has resulted in either users having their @facebook.com address being listed or simply having all of their other addresses be hidden. It happened to me as well.
While users can opt out of having their @facebook.com address listed, the troubling part of the change is how Facebook went about implementing it. The social network didn’t as much as announce the change was coming or alert users once it happened.
To change back your email address, go to your profile, click “Update info,” scroll down to “Contact Info” and click “Edit.” Select with whom you want to share each individual email address and to the right of that choose whether you want your email displayed on your timeline or not.