Evri, a Paul Allen backed semantic search engine, is launching into a limited beta tonight. Evri was first shown publicly at the D6 conference. Evri's CEO Neil Roseman likes to talk about Evri in terms of organizing content instead of calling it a search engine. At its core, however, Evri definitely is a search engine, though it adds a very sophisticated semantic layer on top of its results that emphasizes the relationships between different search terms.
In its early stages, Evri is only going to start out with a limited set of results and possible search terms, based on what it considers to be the most popular terms and people. This approach of starting with only the most popular terms is reminiscent of Mahalo. However, unlike Mahalo, which relies on paid editors and volunteers to create its results, Evri completely relies on its algorithms to create connections between people, products, concepts, and events.
Evri especially prides itself for having developed a system that can distinguish between grammatical objects such subjects, verbs, and objects to create these connections. In his demo at D6, Roseman described the system as being similar to "an army of 7th grade grammar students graphing the Web."
Evri is entering in direct competition with a number of recent entries to the semantic search market, especially Powerset and Hakia. Powerset, however, only indexes Wikipedia articles, while Hakia tries to index all of the web, but focuses less on the relationships between objects and more on providing highly organized results for a given term.
You can sign up for invites to Evri on their homepage. The first wave of users should be receiving invites tonight.
For a more in-depth look at the state of semantic search, see also Alex Iskold's article on the myth and reality of semantic search.