Facebook has now integrated the new emails of @facebook.com, to promote usage of its own email that is linked to the messages in each profile. This has resulted in many users main contact email being changes for them.
This was picked up and reported by bloggers on Saturday, and has now been buzzing on major social media sites.
Another possible reason for this move is to limit the access to public users, to users main direct contact email addresses. of course, the emails are the mainstay of the database business model of facebook, and any limitations to such by public users, is a strategic move by facebook.