Clay Shirky, a professor in the Interactive Telecommunications Program at New York University, points out that Google itself is already a form of social search, due to its dependence on links. "I think the question is, what value do you get out of being more explicitly social?" he says. Since personalized results are one of Delver's main selling points, Shirky says, it's important to be aware of when a user wants personalized results, and when that might not be desirable. "The further we are away from our own areas of expertise and concern, I think the less we care that our results be different," he says. "If I want to know what happened in the Crimean War, and you want to know what happened in the Crimean War, we're pretty happy that the Wikipedia link is the number-one link, because we'll get a good overview. If you're a Crimean War scholar, on the other hand, you're probably not happy about that."

Shirky says that he is suspicious of the claim that social search sites can return better results for general search queries. "People's tastes are more different than the same in environments with large amounts of freedom," he says. He worries that social search results to a general query like "music" might return either a cacophony of songs that would be all over the map in terms of style, or a list of the top 40 songs no one needs to search to find. A better situation might arise for someone looking for "bluegrass music," Shirky says, provided the user is someone, such as a bluegrass musician, who is likely to have a network well versed in the subject.

Agmon says that Delver plans to make money by serving up personalized advertising along with its search results. The company also hopes to get income by licensing its search technology to socially oriented sites and by bringing up more meaningful search results within those sites. Delver is slated to launch next month, after its crawlers have had more time to collect data. Agmon says that he expects to open the site for an invitation-only preview by May.