Live Matrix, the guide to scheduled live online events from video concerts to private auctions to gaming contests backed by Nova Spivack, founder of Radar Networks’ and the Twine semantic web service, officially launched today.

The service, which The Semantic Web Blog first explained in detail here, makes its official debut just as comScore reports that the amount of time Americans spent watching video for the major live video publishers has grown 648 percent to more than 1.4 billion minutes. Also, it says the average live streamed video view is 7 percent longer than the average online video view.

Of course, Live Matrix isn’t just about video events – in fact, Spivack says he believes the service now provides the largest and most comprehensive schedule of private sales on the web.

Operations in private beta mode began in May, and feedback from these users has resulted in enhancements that include new social profiles for seeing what events friends have RSVPd to and what event channels they subscribe to; a streamlined process for saving events and inviting friends; and the ability to see more of the events (some 100,000 top-level events are displayed weekly for public consumption) coming down the pike in the scheduler interface grid. (In fact, some two to three times more than that number of top-level events per week are indexed in its database, for future use.)

What may grab even greater interest among semantic web enthusiasts is that the service will make good on Spivack’s comment (covered here in The Semantic Web Blog’s story on the private beta launch) that it would bring faceted searching to the mix. Giving users the ability to drill into each aspect of an event and search for those sub-categories as well as events will be another boost to improved search capabilities – a beta user request that the company says has already resulted in surfacing better top-level content categories and enabling more personalization.

Faceted search should happen by year’s end. “When you use XML you get into semantics, though it’s probably not portable to other services, while RDF and OWL provide a way to share your semantics,” Spivack says. But “there’s a rich data set in XML, so there’s a whole bunch of metadata and fields and facets, and you can expose those semantics to the user in a way they can do rich faceted search.” There haven’t been requests so far to add interoperability between Live Matrix and other services, so the focus is on first exposing the semantics to the user. Adding a SPARQL endpoint to an API to make the semantics open could be a future option. “But we don’t need to do that right away,” he says.

Spivack mentioned previously to The Semantic Web Blog that, along with Plancast, Twitter, and Facebook integration were on the roadmap, and these are now available. As with most every site on the web now, users of course will be able to use the Facebook Like feature to share content from the site with their Facebook stream, and “we are planning to look at what we can or will use in terms of longer-term Open Graph capabilities,” says Spivack. “It’s interesting for personalization–if a person registers with Facebook Connect and gives access to their profile data, you can tune the site to them based on that.” Knowing from the Open Graph data what users like or not can spruce up recommendations around the content of events or searches.

Likes for events – as well as saves or other engagements with them – also play into scores for events that are generated in real time. Better scores for events lead to their getting higher profiles on the site, which is good for their promotion and for monetization opportunities, as well. The service still has in its sites adding predictive analytics based on user interest in events, which can be valuable information for content providers to capitalize on their engagement, as well as marketers and advertisers to reach target audiences. The service also has enhanced the widget that content providers can add to their sites for their users to access all the Live Matrix features for free on their own page (saving events, for instance, or inviting friends via social networks) – and also contribute to raising the event’s profile and promotion.

Spivack says the service now has a dozen or so content publishers pumping data through, including eBay and ESPN, and in the next release users will be able to supply data to submit an event they like, too. Says Spivack, “It will be kind of like Digg when Digg was good.”

To see Live Matrix in action, you can visit a demo of the service here.

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