It seems like they didn't change your previous preferences but rather added a new one and changed how they interpret preferences as to what is displayed.
If you look at your list of e-mail addresses, it will let you choose who to share it with if it should be shown on timeline.
Previously I had a real e-mail address that was being shared with friends and another real address that was for 'only me'.
When I looked at my preferences today, I saw that those settings remained intact and that it added a third @facebook.com address that was being shared with only me.
I think the second field might be brand new. It says either "Shown on timeline" or "Hidden on timeline" and when I looked today it showed both of the email addresses that I had previously set up as hidden and the new facebook.com one as shown. If they would have just marked the e-mail address that I had set up to be shared with friends as "shown" and added the @facebook.com address as "shown", I (and suspect many others) would be happy and it would still allow them to emphasize that people can use @facebook.com e-mail addresses. (Some people might not like this for spam reasons, but I think this is would be far less evil than what they did.)
Also, since they don't share e-mail addresses via the social graph or have other ways of viewing data, what is the point of differentiating 'show on timeline' with specifying who you share it with? None of the other fields (phone number, IM screen name, address etc.) include this "show on timeline field" but rather set visibility based on the sharing settings. It seems like the "show on timeline" field is completely unnecessary and was only added to get the effect that we're all talking about. (So this was clearly evilness rather than incompetence; for some preference system changes one could argue that it was necessary to 'break' old preferences since the new ones were so different, but that isn't the case here.)
FWIW, I had my real email addresses showing before this weekend and when I checked this morning, the only email address that was being shown was the @facebook.com one. My other 2 email addresses (one visible to each of my friends and one only to a close few) were hidden from my timeline. Shady!!
I can confirm. I had my wife check my account, and she has the most liberal viewing privileges of my profile out of anyone I know. She now only sees a @facebook.com email address. My primary address, @gmail.com, is no longer visible under Contact Info on my profile.
I had the same experience. I don't make my email address public, but I do have it visible to friends - sharing contact info among selected groups is one of the few things Facebook is useful for. When I checked earlier, my real email was hidden from everyone and my friends were only seeing the @facebook.com address.
I'm having the same experience, but I only had a single email address previously (the one I signed up with years ago) and it was visible to friends until this update.
It's safe to assume that the vast majority of users fit this case: signed up with an email address, never added a second one.
Since it affects this use case.. I'm going to posit that this is quite widespread.
Based on reading another post here, I think other e-mail addresses can still be retrieved via Facebook APIs if the user grants permission for them. I was thinking only about the timeline display and the general open graph use cases and neglected the "give extra permissions" open graph use case. Still, I don't see a good reason why there would be differentiation between what is displayed and what is given by the UI (after accounting for who is being shared with) for e-mail addresses versus those other fields.
If you look at your list of e-mail addresses, it will let you choose who to share it with if it should be shown on timeline. Previously I had a real e-mail address that was being shared with friends and another real address that was for 'only me'. When I looked at my preferences today, I saw that those settings remained intact and that it added a third @facebook.com address that was being shared with only me.
I think the second field might be brand new. It says either "Shown on timeline" or "Hidden on timeline" and when I looked today it showed both of the email addresses that I had previously set up as hidden and the new facebook.com one as shown. If they would have just marked the e-mail address that I had set up to be shared with friends as "shown" and added the @facebook.com address as "shown", I (and suspect many others) would be happy and it would still allow them to emphasize that people can use @facebook.com e-mail addresses. (Some people might not like this for spam reasons, but I think this is would be far less evil than what they did.)
Also, since they don't share e-mail addresses via the social graph or have other ways of viewing data, what is the point of differentiating 'show on timeline' with specifying who you share it with? None of the other fields (phone number, IM screen name, address etc.) include this "show on timeline field" but rather set visibility based on the sharing settings. It seems like the "show on timeline" field is completely unnecessary and was only added to get the effect that we're all talking about. (So this was clearly evilness rather than incompetence; for some preference system changes one could argue that it was necessary to 'break' old preferences since the new ones were so different, but that isn't the case here.)