Google+ Shares and Search Rankings
There is fairly wide-spread belief in the SEO community, buttressed by a couple of studies that looked at correlation of rank in Google results vs. number of (incoming) Google+ shares, that getting Google+ shares is an important tool you can use to improve your ranking in search results. Now Eric Engle of Stone Temple Consulting has conducted a high-quality causation study, where shares were introduced and the consequences measured, that shows much more conclusively than before that Google+ shares do not influence search results position. Eric was motivated to do this study by Matt Cutts of Google, who also claims that, despite the common belief, Google does not use Google+ shares to influence search ranking.
Correlation vs. Causation
Just because two items tend to occur together doesn’t mean that one causes the other. It’s possible that Google+ shares correlate with higher search engine ranking because people are finding the content interesting and are creating links to it. So Google+ shares could be correlated with position in search engine results because both are driven by quality content. A good example of a correlation that doesn’t go with causation is eating ice cream and drowning deaths–both of which tend to happen when it’s hot.
Why Wouldn’t Google Use Their Own Social Network?
An obvious question is why Google would not use their own social network for clues to importance of pages, for ranking in search engine results. My own opinion is that use of Google+ isn’t yet widespread enough, so that Google+ shares don’t provide enough data. Which says that we could see this information used in the future, but we do have good information that it’s not used now.
Are Google+ Shares Important?
The study also shows that Google+ shares to appear to increase discovery by Google–that is, if a page isn’t in Google’s index, a Google+ share will put it there. But we don’t need Google+ for this–any good SEO effort regularly makes new Google site maps and informs Google of them, so that indexing of new and changed pages takes place. This can be done automatically and doesn’t even need someone to manually establish a Google+ share.
The Bottom Line
Shares on Google+ should not be the main focus of your Web marketing effort at this time. Given that Google is Google, expect that time to come, but don’t worry about it today.