Personhood and Search Engines

What do search engines know about us? http://searchenginewatch.com/showPage.html?page=2189531

Inside the question of what search engines know about you after you've used them is a question of subjecthood: what kind of person we are and become through our use of search engines. If google records a history of my searches, and uses these to serve certain ads up for me...or even just notices what I'm searching for right now and uses these to simultaneously serve up "relevant" ads, what kind of encounter does a search engine state with oneself or with personhood itself? Does it force people to consider who they are as an aggregate of what they look for online? Or what they go to the internet for? Of what they don't know? Of what they desire? Of what they fetishize? Of what they worry about? Of what they check obsessively? Of what they write about (e.g. uses google as a spellchecker)? Is looking at the ads in AdSense like looking at our own reflection, but as reflected by a mirror of capitalism, in this case, the part of capitalism that strives to make money off of how people search? The capitalization of search, curiosity, desire, unknowing itself?

[note: the kind of unknowing that proceeds and sometimes persists through and sometimes follows using a search engine makes interesting reference to Sedgwick's "privilege of unknowing." Here, the privilege seems to be not heteronormative, exactly, but somewhere in the vicinity of the advertisers who make money off the back of our searches].