"The Relationship Update Stream is an endless feed of social relationship data, designed for web services to be able to send and receive information when changes to social relationships on their service occur." Neat URL, too.

"Your lists of friends and connections on the social websites that you use, sometimes called your social graph, belongs to you. No one company should own who you know and how you know them." This could be interesting!

Facebook's new development platform looks fantastic - very rich, very unusual for its sector.