I was very interested to hear about the launch of Google’s social graph API at the weekend. The social graph API “returns web addresses of public pages and publicly-declared connections between them”, where the connections are currently being obtained from crawled XFN and FOAF links. Dan Brickley, the co-creator of FOAF said:

The Google API looks like a step in a very interesting direction. Of course it will be possible to think of many things it doesn’t yet do, but I encourage everyone here to have a think about simple, practical and useful incremental improvements to it. We can do a lot more eg. with full SPARQL access, but proving full SPARQL to the aggregation of the planet’s public FOAF/XFN data isn’t going to happen anytime soon. Interesting times

In answer to Niall Larkin’s question about how this relates to SIOC, such services help us because by providing an easy method to find one’s social graph (both “me” and “knows” connections), it also makes it easier to find your social objects which can be described using SIOC (see my previous illustration, and see also Kingsley Idehen’s demonstration of how this can work).

In short, you can use FOAF to create the social graph, and use SIOC to represent social objects.

Not everybody is entirely happy (see the comments on Tim O’Reilly’s blog post), with the majority of objections being in relation to the APIs being operated by a for-profit as opposed to a non-profit organisation, and there is some opposition to the idea of a single point of control rather than having a set of distributed indexes.

Perhaps we need something similar to “nofollow” links for the public social graph as well. We will discuss these issues and some other important social network portability topics at WebCamp SNP in four weeks time.

Edit: What I can add to this is my gut feeling that it probably requires a company like Google to make an API that can gather the required momentum and that people will use; previous FOAF aggregator efforts like Plink and FOAFSpace could have done this, but they would have found it much harder to gain critical mass.