Personalized search is just the new
search. Every search is personalized now, no 2 people see the exact same search
results.
For this reason, many people claim that personalized
search is killing SEO as we know it. Not true. While personalized search may cause
tracking SEO to become more difficult, personalized SEO actually makes
optimization easier. You no longer have to be globally relevant where global
relevance is not necessary, only have to be the most relevant for the people
doing the queries