If you are like me, you probably think that XFN and FOAF are really cool ideas that just don’t seem to end up being very useful. Part of the reason for this is that it has been a little difficult for people to understand what the use of the links are, since there aren’t a lot of tools that make cool use of them. While there are applications, they are fairly sparse.
Enter the Google Social Graph API, a way getting easier access to all this linkage data. This still doesn’t answer the question of what cool things can you do with the social network data. (Can I tell you how much I dislike the term “social graph,” by the way?) I totally want to teach a “Leverage a Web 2.0 API” course, where people build mash-ups and API-based applications to wow the world. If I end up teaching the basic LAMP course in the fall, that may provide enough basis for doing a “cool APIs” course after that. Or it might even make up a good final project for that class. Something like Stanford’s Facebook App class.