Google Search Ranking Factors 2012 ( infographic )
There is a lot of discussion around about Google’s search ranking factors. Sometimes these factors are described as a list. They try to rank the factors by importance. The Google algorithm gets more and more complicated. The main question is not, which signals are ranking-factors, but how they're connected and related.
Interesting: "I think the main concept of Google+ is – up to now – the verification of social-users. This is important to get an idea of the power of other social signals. In my eyes Google+ has no effect for Google’s search results."
Author verification (between Google+ and your web site) makes an image and a Google profile link appear in search results. That will certainly help to get attention for your listing, even if the actual ranking remains unchanged.