Microsoft plans to launch a social-search tool this year that will attempt to make search results more relevant by allowing users to direct searches at likeminded online users, reports BusinessWeek Online. Justin Osmer, senior product manager for MSN, says generic search engines can't answer half of queries, and so the time has come for social search - which the software giant hopes will differentiate it from Google and Yahoo and stop its descent in search share.

Microsoft is apparently in talks to buy or partner with startup Eurekster.com, which specializes in social-network search. It combines generic search, via a Yahoo partnership, with information from social-networking sites. Eurekster has two search patents, and six others pending, including for how a search engine can learn from user behavior to how it can make use of collaboration among searchers to derive search results.

Advertisers may pay more to have their ads associated with social searches. Bradley Horowitz, vice-president of advanced products at Yahoo, is quoted as saying social search has more revenue-generating potential, because people typically use social-network searches to conduct e-commerce transactions.