Examples of this include public blogs, update streams, and feeds; and public following/friending relationships. Typically following (one way) seems to be more likely to be public than friending, for social reasons.
Some random notes:
- Public content, once published, should be assumed to be "in the wild" everywhere, indefinitely, until the heat death of the universe.
- PubSubHubHub (prior session) is a great example of a proposed open standard for improving the performance of public social data.
- Problem: How does an author prove authorship of data that's "in the wild" or syndicated? Conversely, how do readers determine authenticity of an authorship claim?
- Blogger's import/export facility currently "wrings the identity" out of the data, because we don't have any way to detect tampering with the supposed author/post/comment data between export and import.
- There was a suggestion that signing a subset of fields in an Atom entry with Google's public key could provide authorship attestation for that data (content, title, author, etc.), in UTF-8 only, which would then let us solve the import/export and syndication attribution problems without having to deal with DigSig.
- Great example of a situation where a hosting web site needed attestation from a chain of 3 parties before allowing possibly copyright-infringing content to be uploaded; no standard exists for doing this online.
- Would like to be able to link to a real world identity (vouched for) or to at least a profile provided by someone like Google; there are lots of pieces of data that would let Google vouch for identity of a profile owner, but no standard way to express this publicly.
- Google for example could also do more general reputation which could also be public.
- A public social graph consisting of following relationships is both useful, and potentially honestly mine-able, assuming users opted in with full knowledge that data was public and mine-able; this is very different from private relationships.
- Public social graph is also potentially a way to determine public reputation; it's possible to game this, but difficult especially if the relationships are publicly visible on the open web so that subverting them believably would take months or years of stealth work.
- Being able to verify past employment, educational credentials, etc. (data that a user chooses to make public and verifiable) would be very useful.