Today Facebook announced Facebook Messages, which bundles together email, chat and text messages to create a single communication stream: "The New Messages: Texts, chat and email together in one simple conversation." If you haven't watched, the Facebook introductory video is below and you can request your beta invite here:
"All your messages together
Get Facebook messages, chats and texts all in the same place. Include email by activating your optional Facebook email address. Control who can send you messages through your privacy settings."