Google have been quoting figures on the number of registered Google Plus users since the launch which have showed a consistent growth.
Google has certainly succeeded in getting people to agree to try Google+ but does this mean it’s a successful social network?
Increased traffic
Referral traffic from Google Plus has not been significant for any site except those publishing a significant degree of high volume unique content.
After an initial buzz period in July 2011 it died down and hasn’t increased significantly as seen here with an example site. As a traffic source it’s completely off the radar.

Google recently introduced authenticated brand accounts which show up for brand searches. This shows an increase in referred traffic but it’s actually existing brand traffic which has been hijacked by Google Plus. Hardly an increase in anything.
The key issue is that there isn’t any significant volume of traffic referred through organic sharing within Google Plus. This is significantly different to Facebook which does drive a continuous stream of natural traffic without the need to publish.
This is the fundamental difference between a social network and a content network.
Increased Exposure
Google plus pages themselves are likely to be pushed further by Google. The recent introduction of Google Plus posts for brand searches is one example.
This has succeeded in driving some additional traffic through to Google Plus and some of it then gets referred on to the brand’s main website.
This results in an apparent increase in referral traffic from Google Plus but this is just an existing brand audience who were sidetracked momentarily. It doesn’t result in any increased exposure to the brand to non-brand aware audience.
Conclusions
Google is desperate to make Google Plus work and is likely to continue adding benefits to the webmasters who play along.
Most webmasters are reluctant to manage another brand channel but likely to tag along fearing they will miss out on a significant long term opportunity.
In the long term Google might increase exposure to Google Plus pages but unless users start engaging with Google Plus it’s more of a content network than a social network.