If the Google+ invites keep flowing, the search giant's social-networking site could reach 10 million users by day's end and 20 million by the end of the weekend, according to Tuesday analysis.
In an attempt to get a rough estimate of Google+ users, Ancestry.com founder Paul Allen (not to be confused with the Microsoft co-founder) has been comparing US Census Data with last names of certain Google+ members. Early estimates released over the weekend put Google+ at about 4.5 million users, but that has since exploded, Allen said.
"My surname-based analysis shows that the number of Google+ users worldwide reached 7.3 million yesterday (July 10)—up from 1.7 million users on July 4th," Allen wrote in a Google+ post. "That is a 350% increase in six days. The userbase is growing so quickly that it is challenging for me to keep up, since the number of users of any given surname (even the rare ones I am tracking) seems to be climbing every day."
More impressive, he said, is that it appears approximately 2.2 million people have joined Google+ in the last 32 to 34 hours, for a total of about 9.5 million people on Monday, Allen speculated.
As a result, he expects user numbers to grow to 10 million today and 20 million by the weekend, provided invites remain open. "As one G+ user put it, it is easy to underestimate the power of exponential growth," Allen wrote.
How exactly is Allen getting these numbers? He said he looked at US Census Bureau data about the popularly of last names in the U.S. and the compared it with the number of Google+ users who had the same last names.
