RSS and RDF are XML standards hatched by the W3C [http://www.w3c.org/]. You can look up the details of those further in your own research, but RSS is a particular extension of the RDF standard that lends itself towards summaries of multiple items on a web page, although it can just as easilly be used for other purposes. Typically an RSS file will be posted on the web ( http://slashdot.org/slashdot.rdf for example ), where clients can regularly update their content to either render that summary into a set of "Quick Links", or slashbox (in the case of Slashdot's engine, Slashcode). It is also possible (although not 100% effective) to repeatedly poll an RSS resource for new items, and bring those new items to attention. This is essentially what Janchor does, it polls a series of sources, and, according to user's interests (individual source subscriptions), forwards those new items as Jabber messages.
RSS is unfortunately not ideal for the purpose of headlines, because of the neccesity of polling. Because XML rendering of this information can be time consuming, most sites (like those running slashcode) typically only update their RSS resource every 30 minutes. This can at times mean that an RSS item may be delayed by as much as half an hour before reaching a client. Likewise, bandwidth considerations make the regular polling of a RSS resource (which can contain theoretically limitless numbers of items) infeasable.
Instead, the main goal of Janchor is to replace the PULL-based headline architecture that many sites have taken advantage of, with a PUSH-based headline infrastructure that will instead see headlines broadcast immediatly upon their discovery, and without the overhead of re-transmission for the purpose of polling. Currently, it appears that this information will be distributed by means of Jabber messages, likely through the use of the "headline" message type and the jabber:x:oob namespace. News sources would operate exceptionally simple jabber servers, which would distribute headlines, via jabber messages, to either other headline components (who could then redistribute them immediately, archive, or otherwise combine and analyse these headlines), or directly to the clients where is is possible and advantageous.
Once a standard means of distributing headines can be developed, and a user base large enough to successfully test the jabber component which performs this task can be generated, and a component that successfully implements this standard is written, one thing will remain: Creation of a simple, secure, efficient server-side package that independant news sites (hopefully with players as large as CNN or the BBC, or general RSS services like newsisfree.com) can implement quickly and easilly.
All of this discussion is still largely experiemental. I would appreciate any feedback into these ideas that you would care to offer, as well as any assistance in development of such standards and software.
Feel free to write back with any questions or comments you have, and thanks for your interest.
- atrus@rifetech.com, email/jabber