Today Ancestry.com founder and “Google+ unofficial statistician” Paul Allen released some updated numbers on Google+ that he calculated since Larry Page announced the 90 million-user milestone earlier this month. Allen said Google+ has grown more than 10 percent since last month and he estimates a new 100.8 million total with the service adding over 750,000 new users every day since Jan. 19.
Allen explained if the growth continues to hold steady, Google+ would hit 345 million users by the end of 2012. However, he also expects Android 4.0 to steadily increase signups and usage, and therefore he is predicting the service will hit 400 million users by the end of the year. In comparison, it took Facebook over four years to hit the 100 million user milestone.