Much has been written about Google’s recently announced +1 service but now Google has added advanced analytical features that could help prove or disprove the value of this new tool.
But first, what is Google +1? At it’s core, +1 is much like Facebook’s ‘Like’ feature. Website owners can add +1 icons like this: 
to their sites that allow visitors to indicate that they like the page. A counter shows how many other people have clicked the +1 button, thereby giving social proof to boost the perceived value of the web page. Importantly for site owners, these +1 votes are also taken into consideration when presenting search results in Google, so the more clicks you get the greater the chances of people clicking through to your web page.
There’s also a social media component to this. Signed-in Google users who click a +1 button leave a trail that shows that they clicked the button. When a signed-in Google user is searching, the Google search result snippet may be annotated with the names of the user’s connections who have +1’d each page. If none of a user’s connections has +1’d a page, the snippet may only display the aggregate number of +1’s the page has received.
What’s new? Google has now gone one step further and added new tools to Google Analytics that allow site owners to show exactly what influence (if any) the +1 buttons have on traffic to a site. As the example screenshot below shows, Google will report how many times a +1 count has been annotated to search results, and what clickthrough rates have been achieved with and without these +1 annotations.
[click to enlarge]
There’s also an Activity Report that shows how many times selected pages have been +1’d and an Audience Report that shows geographic and demographic data about signed-in Google users who have +1’d pages.
These data data points may prove valuable in helping marketers quantify the value of social proof and the impact is has on broader online marketing efforts like search engine marketing and neighbouring display advertising.
My advice: Test +1 on selected web pages and see if these analytics tools can help you measure how people interact with your content. With luck you may be able to establish how much influence social proof has on search behaviour. Just don’t expect quick results as Google’s +1 service has far lower penetration and awareness than Facebook’s well-established ‘Like’ feature and may not have a long term future if it stumbles like some previous efforts.
More reading:
Google Webmaster Central Blog:
http://googlewebmastercentral.blogspot.com/2011/06/1-reporting-in-google-webmaster-tools.html
Web Pro News:
http://www.webpronews.com/google-adds-1-button-data-to-google-analytics-2011-06
Search Engine Land:
http://searchengineland.com/official-google-analytics-gets-social-engagement-reporting-83707
Web SEO Analytics:
http://www.webseoanalytics.com/blog/google-plus1-vs-facebook-like-the-similarities-and-the-differences/