From the introduction:
It was with a great deal of anticipation that I threw in front of them the same question: what will the search results page look like in 2010?Go read the whole thing, but, as usual, I am going to focus here on the part on personalized search.
Here, aggregated and condensed, are their answers.
Chris Sherman, Jakob Nielsen, and Greg Sterling are skeptical about personalization. Personalization "is incredibly hard to do" because "language is so inherently ambiguous" and "you have to guess", not to mention "the so called creep factor."
Danny Sullivan, Justin Osmer, Michael Ferguson, and Larry Cornett are more optimistic. "We're getting close to a tipping point on personalization" where little or no effort ("a very low investment") yields "a lot of return" because searchers will "get a lot more out of [the] search experience" if the search engine knows more about them. Searchers "clicks and their footsteps will walk to the experience that is most delightful and easy for them to use," though we should be careful not to "ask the users to do work." "Google is onto something with their personalized search results," and "people are misunderstanding how sophisticated it can be."
Oddly, Marissa Mayer did not say much on personalized search this time around. In the past, she has said (  ) that "[personalization is] one of the biggest relevance advances in the past few years", "personalized search is something that holds a lot of promise", and personalization is key for building "the search engine of the future."
Similar to what Esther Dyson said in her interview with Charlie Rose, Chris Sherman agrees with Gord Hotchkiss that "Google is holding a significant portion ... of their personalization algorithm in reserve" because there is "caution" that they might "alienate the searcher." Chris goes on to say, "They probably have tons of stuff that they're not showing us."
On personalization being incredibly hard to do, please also see my March 2005 post, "Personalization is hard. So what?"