PubSub has announced the launch of Structured Blogging, a foundation that provides a means to include tags in Web pages and blog postings that identify structured data as rich data, rather than simple text. Using Structured Blogging, users can post an item which is an "Event Announcement" and, because of tags in the item, that item can be identified by search engines as an "Event Announcement" which has fields that can be indexed, stored, and searched for. One of the keys to Structured Blogging is that it lets users format specific content types, so that movie reviews, for example, don't look like calendar entries. Structured Blogging is very similar to an edit form on a blog; the difference is that the structure will let users add specific styles to each type, add links and pictures for reviews.
Once Structured Blogging is in place, users can start building applications on top of it. Because it's an XML format and embedded in both the HTML blog and the syndicated feed, applications can run in Web browsers (like a Firefox plugin for comparison shopping which reads product reviews); aggregators (like an aggregator that adds a friend's calendar entries to your datebook); or Web services (like a feed for everyone who is attending the same conference). Since Structured Blogging is open, anyone can build applications or services based on the structure in each entry. PubSub.com provides a free matching service that continuously reads blogs, newsgroups, SEC Edgar Filings, press releases from wire services, earthquake data from the US Geological Survey, and FAA airport delay information to alert users whenever material events occur. This real-time notification service is made possible by PubSub's proprietary "matching engine."