A9, My Yahoo Search, My Ask Jeeves, and Findory have had this feature for a while. All but Findory require users to sign in to activate the feature. Like Findory and A9 but unlike Yahoo and Ask, Google's search history feature is integrated into the main search on the site.
Keeping search and clickthrough history is a first step toward personalized search. The next big step is to use this data to reorder search results, making the results more relevant to your particular interests and needs.
Personalized search is the future. In his article on Google's new search history feature, Chris Sherman says:
- Don't expect Yahoo, Ask Jeeves, MSN or AOL Search to stand still. Personalized search has long been touted as one of the holy grails for the industry ... Beginning today with Google's launch of My Search History, I expect to see major leaps ahead in the arena of personalized search -- and that's a good thing.
[See also Stefanie Olsen's article at CNet]
Update: Charlene Li says personalized search results are the "Holy Grail of search" and quotes Google Director Marissa Mayer for an example of how Google might personalize search results.
Update: Danny Sullivan posts an interesting comparison chart of search history features from A9, Ask, Eurekster, Findory, Furl, Google, and Yahoo.