Google+ is really having huge impact on Search results. It is giving Instant boost in SEO of website's for People in their Circles. They will see all the Updates by you in their Profiles as well as Ranking of the content you share will be increased in Google search results instantly.
In my websites, google+ doesn't have any work on high rankings and traffics. the only thing i noticed was, it help me indexed faster.
Having a Google+ profile will definitely help in improving your page rank and also your ranks on the search results.