Just a quick one today. If you really want to bury your head in high-level technical search stuff, I can’t tell you how much I recommend Bill Slawski’s blog SEO by the Sea. He basically analyzes patents that Google has filed and released, and tries to talk about the impact they may have on modern search.
Last week, Google published a new patent that shows more insight into how they think about personalized search. Bill wrote up an awesome piece on it. Rather than even attempt at trying to explain it, I recommend you just go check it out on his site: Google’s User Profile Personalization and Google Plus.