I am surprised this didn’t get broader attention, it sounds pretty cool. Basically, as I understand it what this does is enable the creation of semantic data within web pages, blogs posts, or any other kind of content by tagging it as you write it. In much the same way that hyperlinks establish a “relevancy relationship,” this will enable better search relevancy by tagging key words, such as people names.

Something else struck me about this initiative. Reuters has made a significant investment in what we would generally call semantic technologies over the years. Calais is kind of like Amazon Web Services, minus monetization, in that it opens up to external developers the same technologies that Reuters itself is using.

The Calais Web service enables publishers, bloggers and sites of all kinds to automatically metatag the people, places, facts and events in their content to increase its search relevance and accessibility on the Web. It also lets content consumers, such as search engines, news portals, bookmarking services and RSS readers, submit content for automatic semantic metatagging that is performed in well under a second.

[From Reuters Releases Open API for New Calais Web Service: Financial News - Yahoo! Finance]