Google+ doesn’t have the user base or marketer interest of Facebook or Twitter, but its connection to search results is causing marketers to closely watch the growth of the site.In September 2012, Google announced that 400 million people had signed up for Google+ worldwide and that there were 100 million actively monthly users. But according to an August 2012 study from SEO software provider SEOmoz, only 54.9% of online marketers worldwide said Google+ was one of their top five most-used sites for social media marketing, compared to 87.7% who cited Facebook and 82.7% who cited Twitter. Google+ did, however, come in above YouTube, which 48.9% of respondents cited.