Tamar Weinberg at Search Engine Roundtable has good notes on the "Personalized Search: Fear or Not?" panel at the recent SMX conference.
Matt Cutts from Google and Tim Mayer from Yahoo were on the panel. From the notes, it looks like it was pretty interesting.
Gord Hotchkiss, who was also on the panel, has a post with his reaction afterwards. It sounds like the audience, who were mostly search engine optimizers, were fairly hostile to personalized search.
That is not surprising. By reducing the winner-takes-all effect, personalized search will make search engine optimization more challenging and subtle.
For more on winner-takes-all and personalized search, see also my previous posts, "SEO and personalized search" and "Combating web spam with personalization".