This is really cool – I’ve been running an internal beta build of it for a while now. You can now see Facebook status updates for anyone who sends you mail, depending on their privacy settings. Get the Office Social Connector 1.1 here:
Then, install the Facebook connector, which you can get here:
Angela’s got a good write up of all the details, including screenshots, and what you need to know if you want to write your own connector. Read about it here.