Very interesting change: Facebook closing @facebook.com messaging service
This is a very interesting change, because so far the @facebook.com email was practically useless for marketing reasons, since all messages were dumped in "Others" folder without notification. But, now all messages will be forwarded to primary user email. So, if someone has a list of @facebook email addresses, can send his message and this will be properly delivered to the user's main address. Game changes again...
Full article: Facebook closing @facebook.com messaging service after small usage - Pocket-lint