celgins - 1:17 am on May 24, 2011 (gmt 0)
This is the single most evil thing I've seen in terms of its impact, if in fact social signals (in essence a measure of POPULARITY, not quality) play anything but a minor role in SERPS.
I don't recall anywhere in the history of the Internet where a company stated that it would never change or adjust its business model to appease the populace. Whether it's based on money, emerging trends, or something totally different, Google and Bing are simply making adjustments to see just how popular social SERPs can be.
Think about it: In the past, there were only a few ways to recommend an article, a page, a piece of content, or a website. You had to link to it, and that was typically done through other websites which built popularity and authority. Now with social media, individuals, not just websites, can play the suggest/recommend/I-like-this game by helping Google and Bing build popularity profiles.
Some might even argue that if a website's content is truly great, thousands of folks will Like it, Tweet it, Stumble Upon it or Mixx it. So instead of authority being the main signal for SERP dominance, Google and Bing are considering popularity as a stronger SERP signal.