We're trying to paint personalization into a corner based on Google's current implementation of it. And that's absolutely the wrong thing to do.Right now, relevance rank must rank according to the average need. But, different people have different interpretations of what is or is not relevant. It is getting harder and harder to find improvements while still serving the average need.
Personalization is not a currently implemented algorithm ... [It] is an area of development.
Personalization, in its simplest form, is simply knowing more about you as an individual and using that knowledge to better connect you to content and functionality on the Web.
There are many paths you can take to that same end goal .... To win, Google doesn't have to do it perfectly. It just has to do it better than everyone else.
At some point, the only way to further improve the quality of search results will be to show different people different search results based on what they think is relevant.
At that point, we have personalized search. Showing different results to different people based on what you know of their interests is personalized search.
There are many approaches to do personalized search. To the extent that Google's current algorithm is based on the Kaltix work, it is a coarse-grained approach, building a long-term profile which then subtly influences your future results. I tend to prefer a fine-grained approach that focuses on short-term history to help searchers with what they are doing right now.
Yet those are only two of the possibilities of how knowing more about a searcher's interests could help improve relevance. Google's implementation is not the only path. There are many ways to show different people different results based on their interests, some of which could prove more helpful than Google's to searchers.
See also some of my earlier posts (  ) where I criticized Google's approach to personalized search and discussed an alternative.
See also my March 2005 post, "Personalization is hard. So what?", where I said that personalization "doesn't have to be right all the time. It just needs to be helpful."