And while Google+ is making great strides in bringing visitors to the site, it's still distinctly behind major social networking players like .

By comparison, had 8.2 billion U.S. visits in August and 7.65 billion in September. And Hitwise reported that had 172.9 million U.S. visits in August and 144.9 million visits in September.

"The numbers for Google+ are good, but it's not really a challenger to Facebook yet, although the numbers are big enough to warrant advertiser attention," said Dan Olds, an analyst with The Gabriel Consulting Group.

Olds added that every time , as it did by tracking some users even after they had left the site and by launching yet another unpopular site redesign, it's an opportunity for Google+ to only look better by comparison and pick up a few more users.

Rob Enderle, an analyst with the Enderle Group, noted that Facebook's won't force a mass migration from that site to Google+, but each instance is cumulative.