Google, Yahoo! and MSN dominated search engine world changing based on user behavior and new competition.

New styles of search have been launched by: Clusty.com, Blinkx, Snap, A9.com, Info.com, and a much-revived and revamped Ask Jeeves, reports EContent.

Google launched its own desktop search tool, Yahoo! with a new personalized search service, and MSN has some new tricks up its sleeve to help users get to content.

EContent reports that Google are seeing important shifts in user behavior; many users now put URLs into the Google toolbar search box in order to get to a target site, which suggests that surfers are starting to use search engines as reliable modes of navigation, not just as data harvesting tools. This means that search engines are starting to see themselves as portals, as entryways to the Web, and so we see them partnering more feverishly with content. Google recently bought mapping service Keyhole and allied with BellSouth's RealPages.com to sell local AdWords advertising.

MyJeeves at Ask.com and Amazon's A9.com retains users search history, even bookmarks, for easy recall and building of the users' preferences, which is valuable to advertisers, especially if the search engine can follow the user with targeted ads as they move off of the results page and into the content destinations.

Many search engines now let users tweak the very algorithms by which results are ranked. Snap.com gives you the option to rank listings according to their popularity with other users and even according to the length of time previous users spent on each destination site after clicking through.

Clusty.com, organizes search results into a series of topical folders, so that relevant listings that might have been pages deep in the results have a better chance of coming to the surface. According to some leaked screenshots of experiments at MSN Search, that upcoming engine may have sliders for fine tuning the rank order according to popularity, timeliness and search term matching.

It is anticipated these changes will cause vendors and content providers to move from low cost search optimizing to higher cost keyword ad buying to ensure search engine exposure; the ways companies advertise on engines and plant their advertising; in the way they optimize content to ensure its placement in results; and in the way they seek partnerships with search engines as they start re-positioning themselves as portals rather than mere tools.