Most critics believe Google+ is gaining popularity online, but at least one study figures Google's latest social experiment is growing at rates that rival Facebook's. The search giant's two-week-old social network, currently in a limited field test, reportedly grew by 350 percent between July 4 and July 10 from 1.7 million users to 7.3 million. Google+ is also set to hit 10 million by Tuesday and 20 million by the weekend, according to one study.
Those growth numbers assume that Google won't restrict users from inviting their friends this week, as Google did the week prior.
The Google+ population estimate comes from Paul Allen, founder of Ancestry.com, who posted his findings on (where else?) Google+. Allen based his work by counting surnames on Google+ and then comparing that count to Census Bureau data.
If he's right, then Google+ is currently signing up an average of more than one million new people every day since its June 28 launch. By comparison, Facebook in 2009 -- arguably the height of the social network's rapid growth -- was gaining nearly a million new users a day, according to The New York Times.
Google has yet to officially announce how many users are on Google+.
Allen started his work by comparing Census Bureau data about surname popularity to US Google+ users with each surname. Then he took a sampling of 100 to 200 surnames on Google+ to estimate what percentage of the US population is on the new social network (he didn't disclose that number). To get the international Google+ population, Allen assumed there were 2.12 non-US users for every American on Google+.
Allen maintains his model by tracking the growth rate of a smaller sampling of 100 unusual US surnames on Google+. He then assumes a similar growth rate for the rest of the surnames in the US on Google+ and then multiplies that estimate by 2.12 to get the international user count. Allen doesn't claim his estimate is perfectly accurate, but believes his numbers are at least in the ballpark. It's an interesting approach to estimating Google+ users and one you would expect from a person with such a deep interest in genealogy.
Whether you believe Allen's approach is valid or not, Google+ does appear to be popular and is still at the height of its love affair with the tech press.
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But even if Google+ is growing at an incredible rate right now, it's not clear how many of those Google+ users are signing on to use the service regularly. Facebook says it has 750 million active users; however, the world's largest social network doesn't say how often someone has to interact with Facebook to be considered an "active user."
The other question is whether Google will be able to sustain Facebook-like adoption numbers over the long term. Google+ may be gaining an incredible number of users every day, but will those people stay to use the site or just sign up, try it out and leave?