Social search engines haven't exactly taken off. But that's not stopping OneRiot to apply this concept to video search.

OneRiot, a social search engine launched in November 2008, plans to launch Tuesday a video "social" search engine.

The video social search engine is designed to deliver the most talked about and viewed videos in real-time. It’s attempting to provide a “real-time index of the social Web,” said Tobias Peggs, general manager of OneRiot.  Essentially, OneRiot wants to be the destination where people go to get the “pulse” of the Web. About 40% of Web searches are people trying to figure out what’s going on at the moment, said Peggs.

Indeed, most search engines, while comprehensive, are not designed to serve up relevancy, based on real-time popularity or buzz. 

The question is, does OneRiot have a broad enough user base to get the pulse of the Web? And, how exactly does it measure the pulse?

It appears the user base is skewed toward the college crowd, or 18-24 year-old demographic, suggesting the results may not exactly be what an older demographic finds relevant.  

OneRiot determines what’s buzzing online by mainly observing the activities of those who’ve opted into the OneRiot service to have their activities aggregated anonymously, said Peggs. About two million people have already downloaded the company’s toolbar, which has been available to download since two years ago when the company launched initially as me.dium, a social surfing tool to surf the Web with friends. Many of those who've opted in skew younger. In fact, to broaden its reach OneRiot is going to college campuses to get student representatives to do some grassroots marketing. At the moment, OneRiot has 80 campus representatives working for free and handing out t-shirts or giving OneRiot demonstrations.

OneRiot then monitors the activity of their users if they go to certain sites, like Twitter, Digg or the top 30 video destinations, such as YouTube, Hulu, Metacafe and Vimeo. The top-ranking video results are based on views, and freshness of activity. The demographic is skewed to 18-24 year olds, said Peggs.

With the popularity of Twitter, it's clear that people want real-time information and a way to find out what's being talked about online.  But, with its own search engine, Twitter is as close to a social search engine as they come. Peggs said that while Twitter shows who's talking about topics, it doesn't identify the actual piece of content about a topic that's being viewed or discussed the most. He's got a point.

But social search is a tough service to deliver. It's been tried and done before. It's not to say that there won't be anyone to succeed in this space. It's just that getting enough users to download OneRiot's toolbar or opt-into this service may be a big challenge.