Raul Valdes-Perez of Vivisimo begs to differ with all the hype around personalized search (including in my book), and the idea of major engines mining your clickstream to better understand your intent (and give you more personalized ads, of course). In a short paper outlining his views, (PDF download), he outlines five major problems with personalized search and concludes:
…. search personalization is likely to waste the talents of top computer
scientists. It may even give worse results…