Dubbed 'My Web 2.0', the service builds on personalised search features introduced in late April. While those features allowed Yahoo users to archive their search results and share them with other users, the next iteration will go further.
Those with a Yahoo login will be able to bookmark and cache copies of their favourite Web sites, label them in certain categories and attach comments in a structured way. Users will then be able to search among their contact's knowledge base with what Yahoo is calling its MyRank search technology.
"Over time, you will see us integrate MyRank technology across other Yahoo! applications and services," the company's search team wrote on its official search blog yesterday. Users are also to import their existing bookmarks into their online listings.
In many respects the service bears a resemblance to the del.icio.us Web bookmarks manager, which has recently been gaining popularity. Like del.icio.us, Yahoo has opened My Web's application programming interfaces, allowing extensions to its service to be easily created.
Akin to del.icio.us, Yahoo's service is best used when integrated with a user's browser toolbar.
The company said it created My Web to deal with three problems facing the online search market today.
Firstly, the company said, search engines were limited in their ability to answer opinion-based queries such as the definition of the best plasma television review site, because search engines were impersonal and did not capture "the opinions and recommendations of the friends and authorities" searchers trusted.
Secondly, search engines were not able to always interpret the meaning of a user query. For example, a user searching for The Beatles' record label Apple Records might instead be directed to the more generally popular Apple Computer Web site.
The third shortcoming was a more nebulous problem.
"Today's search engines can deliver great results ... but typically do a poor job of connecting you with new items that might be interesting, timely and personally relevant. Your friends and people who share common interests with you are better sources for this information," said Yahoo's search team.
The company is ambitious in its long-term aims for My Web.
"Over time, we envision communities using My Web to build their own search engines to capture and make accessible the knowledge of their community," the blog waxed enthusiastically, giving the example of search engines populated by knowledge from groups of medical researchers or a bird-watching club.
Yahoo is facing stiff competition from Google, which yesterday launched a new version of its own personalised search that monitors previous searches to refine future results.