Facebook not lets you receive encrypted email messages, just add your PGP key to your Facebook profile.  This is a good step in the right direction for making the internet a more secure place.  But my main concern is not many people use PGP, so I doubt that a lot of people will make use of this feature.  Of all the people I have met, one or two people have given PGP a go and they do not use apart from the occasional encrypted message.

https://www.facebook.com/notes/protecting–the–graph/securing–email–communications–from–facebook/1611941762379302“>Link to Facebook Post