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The Google +1 button is out, so the question arises – should you include it on your site?

First, let’s take a minute to consider what it does. The plus one button allows you to share content with friends in your network. If you click it on a page or next to a result in search (such as at the bottom of this page or in the search result shown in the screen shot), friends in your network (ie your Google account contacts) will be able to see this if the page shows up in search engine results. As of today Google has not given any indication of whether it will impact search rankings: you can read Google’s description here. It is indeed a play on behalf of Google to gain more social graph data and to make search results more interactive.

But they have in the past indicated, and tests have shown correlation that sharing links on Twitter and Facebook Likes do impact search rankings.

My take on this is that Twitter and Facebook buttons are still much more powerful in driving traffic than the Google +1 button due to their viral effect and especially Twitter’s correlation with search rankings. But if you want to install a third button, Google +1 would be a good one to consider. In addition to making a result stand out a bit more in the SERPs, it may in the future impact search rankings. Although at this point in time it is not possible to show relevance to a given search term with an on page +1 button, its use would make a good popularity metric.

Therefore we can consider that it is at least a possibility that Google will make +1 button clicks a factor in search ranking algorithms in the future as a popularity metric once the button is out of beta test mode. If they do in fact go this way, you can get ahead of the competition by adding the button now. At a minimum it will make your current rankings slightly more visible to certain people.