Patently Apple discovered a recently published Apple patent detailing an "Add Contact" workflow and "Social Networking" workflow that specifically uses Facebook as it's main example. Now that does not mean this patent will not work with other social networks, but Facebook is the current king of the mountain and it makes sense considering that it was just last week heard Apple was looking to integrate Facebook into iPhone OS 4.
With the deep integration of social networking sites on various Android-based devices Apple does have some catching up to do. We all know, when Apple takes their time the final product usually tops all other implementations out there. Cut/Copy/Paste ring a bell? Good things come to those who wait.