Google's infant social network experienced a recent growth spurt. Google+ has more than 90 million registered users, Google CEO Larry Page said during the company's earnings presentation on Thursday. That more than doubles the 40 million that Google reported in October. "We're very excited about the growth we've had, and we've certainly seen a tremendous number of people added every day," Page said. "That notion of identity is a deep part of what we're doing." Google launched its social network last June. Since then, it has added toolbars and other buttons on its websites to aggressively promote the service. Google stirred up controversy last week when it began giving prominent placement to Google+ pages in results delivered by its search engine. On average, Google engineers have introduced a new feature related to Google+ every day since its launch, Page said. It took Facebook about four years to reach 90 million users, according to Facebook's public statements. After starting as a students-only service, Facebook now has 800 million people checking their accounts at least once a month, about 10 times that of Google+. Analysts say Google+ was built specifically to challenge Facebook's growing dominance on the Web. Google and Facebook generally do not collaborate. Another rival social network, Twitter, complained that the recent changes to Google search favor Google+ and harm Twitter's ranking on results pages. "We provide a lot of third-party data in search, and we would love to have more," Page said in response to an analyst's question. "Generally, companies have been walling that data off." People who register for Google+ tend to be dedicated users of Google's search engine, e-mail and documents services. More than 60% of them use Google products every day, and 80% visit a Google site at least once a week, Page said. Page, who posted his comments on his Google+ page, did not say how often or what percentage of users specifically visit its social networking service. "Engagement on Plus is also growing tremendously," Page said. A Google spokesman declined to comment.