I’m happy to say that we have recently described and shown how this can work. Alex has been the driving force behind a paper that we (Alexandre Passant, Tuukka Hastrup, Uldis Bojars and I) have written for SFSW 2008, demonstrating (a prototype called SMOB for) distributed / decentralised microblogging:
The prototype uses FOAF and SIOC to model microbloggers, their properties, account and service information, and the microblog updates that users create. A multitude of publishing services can ping one or a set of aggregating servers as selected by each user, and it is important to note that users retain control of their own data through self hosting.
The aggregate view of microblogs use ARC2 for storage / querying and Exhibit for the user interface. Security and privacy are open issues, but can be addressed in some part by requiring OpenID authentication.
The SMOB prototype code (both the semantic microblogging publishing client and server-based web service) is available here. You can install your own client and post to our demo server (set up today by Tuukka) here. There are some pictures below of it in use:
Latest updates rendered in Exhibit
Map view of latest updates with Exhibit
Global architecture of distributed semantic microbloggging