The way data is “picked up” from various sources to give users the best data for search has changed over the years. In the beginning it used to be straight up blogs, which were supposed to be the best possible updated source of information for a company of person. That has evolved—we have information coming from so many sources, and now the search engines display the latest information from a wide array of sources.
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SEO predictions 2010—“Social-recommendations” and personalized search

