A complete surprise, Facebook is launching an new message service called Titan. They are also providing an @facebook.com email address to every person on Facebook who wants one. Now people can share with friends over email, whether they’re on Facebook or not. To be clear, Messages is not email. There are no subject lines, no cc, no bcc, and you can send a message by hitting the Enter key. They claim to have modeled it more closely to chat and reduced the number of things you need to do to send a message.
Obviously there are some inherent privacy risks associated with lumping all your contacts and emails into one space, especially when Facebook does not let you export contacts to Gmail etc. This is doubly so when Facebook have been accused of some breeches of privacy in the past.