• by Laurie Sullivan , Staff Writer @lauriesullivan, July 21, 2011

Paul Allen, the Google+ unofficial statistician and founder of Ancestry.com, estimates Google+ members at nearly 20 million. The site launched less than a month ago. Not only are data companies scrambling to build apps that analyze social traffic and profiles, but developers want an API to link in.

Allen is not the only one obsessed with estimating Google+'s growth, although during Google's quarterly earnings call last week CEO Larry Page revealed that Google+ -- at just more than two weeks old -- had already reached 10 million members.

More than 77,923 engineers, 12,511 programmers, 5,459 musicians, and 1,250 doctors use Google+. That's according to a sampling of stats from FindPeopleOnPlus.com based on a sample of a little more than 4.5 million users. The majority of Google+ users live in the United States, followed by India, Brazil and the United Kingdom.

Most of the users work in or write about technology, according to FindPeopleOnPlus.com. The top 10 companies represented by Google+ users include Google, self-employed, IBM, Infosys Accenture, Tata Consulting, Freelance, Microsoft, Apple, and Cognizant. It's interesting to note that IBM, Infosys Accenture, Tata, and Cognizant all support IT consulting services in their respective businesses.

With this type of available data, companies such as CareerCast suggest Google+ will become a strategic social media resource for companies looking for talent, becoming as important than LinkedIn.

Facebook execs are not the only social media advocates keeping an eye on Google+. Earlier this week, speaking at a Churchill Club event, Computerworld reports that LinkedIn CEO Jeff Weiner said Google+ will fail after being asked whether there is a limit to the number of social networks that can successfully exist.

The problem with other social networks is they keep a member's professional and social life separate. Google+ combines the two.

So after seeing a plethora of data coming from a variety of sources, brand marketers might think more along the lines of audience segments and ad targeting and retargeting one Google ads advertising and business profiles.

Google+ received more than 1.8 million visits in the last week ending July 16, 2011 -- up 283% compared with the previous week and up 821% compared with the week ending July 2, according to Experian Hitwise. The data firm said Google+ ranked No. 42 as the most-visited social networking site in the U.S. for the week ending July 16, 2011, up from 683 in the prior week.

But marketers won't need an ad tag or Web site tag to determine where Google+ visitors originate. About 56% of traffic to the social site came from Google properties, with about 57% males, and 38.37% of visits from users ages 25 to 34. Most visits came from the Los Angeles area, followed by New York City and San Francisco, according to Experian Hitwise.