Yihong Ding from Brigham Young university wrote an article on the evolution of websearch (search 3.0). There's an interesting challenge from Haika engine's Riza, countered by Yihong. Hakia is a good engine but has yet to evolve, which is a good thing, there's improvement ahead.
Yihong proposes a criterion by which to evaluate search engine performance. He explains "every evolutionary stage of Web search can be uniformly determined by the quality of its produced link resources. In specific, Search 1.0 means the produced link resources are 1.0-level quality, Search 2.0 means the produced link resources are 2.0-level quality, and so on."
In his opinion, almost all search engines belong to search 1.0. Hakia claim to be doing search 4.0 however Yihong responds with "The criterion to measure stages of evolution is not about how well the search results are but about in which quality of productivity the search results are produced."
Food for thought and debate clearly.