…of course, not really, but with the addition of Google Plus Your World to the world of search, Google has just editorialized search with the opinion of your friends on Google Plus and it has heavily weighted the Google Plus profile links. (MG Siegler does a wonderful job of calling BS here: http://parislemon.com/post/15682237911/twitter-keeps-right-on-responding-to-search).
But Google has completely killed the world of SEO…again. Google did deal SEO a tough hand when they started to personalize results. And with the advent of universal search, the prominence of organic search results was greatly diminished. But with the smothering of Google + detritus on, in and throughout the SERPs, Google has done away with the algorithmic results that were reasonably neutral. Now, the SERPs are filled with suggestions for Google + profiles, and when appropriate, images from your social contacts photo streams. The issue that has serious implications for Google as a business is the overwhelming presence of Google properties in the results. This is likely an issue that will get figured out over time. Right now, Google + is prominently featured, and as Google’s point of connection for its services, that makes sense. But the diminished visibility or downright exclusion obviously more relevant results (see either MG’s article above, or Alex Macgillivray‘s example here.)
But with regard to SEO, the addition of all of this social information has made the organic links harder to find, which really diminishes the advantage of having premiere search visibility. But beyond this, the algorithm is so very personalized that discovery may be diminished (see Eli Pariser’s treatise:The Filter Bubble for a deeper discussion). But SEO has died because the efforts of the marketer or publisher to create an authoritative site is lessened because of social signals that influence the presentation. Let’s face it, we are creatures of limited attention, so the vast majority will take what is served up, rather than hunt for the best answer.
So, yeah, Google killed SEO as we know it. But rather than being dead, SEO will simply evolve.