Facebook Officially Passes the Half a Billion User Mark

Updated: Facebook now has over 500 million registered users, CEO and co-founder Mark Zuckerberg announced in a blog post today, calling it “an important milestone for all of you who have helped spread Facebook around the world.” In the last 18 months Facebook has more than tripled in size. Less than six months ago, the social network passed the 400-million-user mark, and at the beginning of last year it had just 150 million registered users. In honor of passing the half a billion mark, Zuckerberg also launched a site called Facebook Stories, where users of the network can upload their thoughts about how it has affected their lives, and a feature containing messages of thanks from Facebook employees.

Even with its prodigious growth rate, Facebook has suffered more than its share of growing pains — particularly over the past year, as it launched its “open graph platform” aimed at extending its social graph plugins to millions of websites, and fought multiple governments and privacy advocates over changes to its user settings. Zuckerberg, meanwhile, has gone from being the archetype of the twenty-something web entrepreneur to being the subject of unflattering behind-the-scenes stories about the rise of the social network, both in a book and a forthcoming movie. And while it may be huge and growing, Facebook still has work to do in terms of consumer satisfaction, according to a recent survey that ranked it behind both the airline industry and the cable TV industry.

Update: Facebook’s CEO has said that the network plans to continue growing just as quickly as it has been over the past year, telling attendees at an advertising conference in Cannes that he expects the company to reach the one-billion-user mark, calling it “almost a guarantee.” And as it has grown, the social network has become more popular with advertisers — the company told Bloomberg last month that the number of advertisers it was working with had quadrupled in 2009, and numbers from eMarketer show that worldwide advertising on Facebook grew by almost 40 percent last year, to $600 million. The site has also been working on building results from all of the social-graph plugins and “like” buttons into its search engine, which some believe could become a strong competitor for Google.

Facebook’s current statistics include:

* 50% of active users log on to Facebook in any given day
* Average user has 130 friends
* People spend over 500 billion minutes per month on Facebook
* Average user is connected to 60 pages, groups and events
* Average user creates 70 pieces of content each month
* More than 25 billion pieces of content shared each month.
* About 70% of Facebook users are outside the United States
* Every month, more than 70% of Facebook users engage with Platform applications
* More than one million websites have integrated with Facebook Platform

Embedded below is a video of Mark Zuckerberg introducing Facebook Stories:

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