"It's a platform that has survived and grown despite its privacy issues, usability issues and security problems," said Brad Shimmin, an analyst at CurrentAnalysis.
"Facebook has shown that despite struggling in a number of key areas, like generating money off its , the company has been able to maintain and grow a very valuable user base," he added.
The growing user base, Shimmin said, is an indication of the human need for connection and how it's now playing out electronically.
"We're asking ourselves: What do you even compare this to? There's nothing. There's just nothing," he said. "We're entering new territory here with this kind of milestone."
Facebook CEO Mark Zuckerberg Thursday said that the social network reached the 1 billion active monthly user milestone at 3:45 a.m. EDT on Sept 14. With that total, one out of seven people on the planet are now Facebook users.
"Helping a billion people connect is amazing, humbling and by far the thing I am most proud of in my life," Zuckerberg wrote in a on Facebook. "I am committed to working every day to make Facebook better for you, and hopefully together one day we will be able to connect the rest of the world too."
Easily the most popular social network in the world, Facebook said it has seen 140.3 billion friend connections, 219 billion photos uploaded, and 62.6 million songs played 22 billion times, adding up to about 210,000 years of music.
"This means that whatever problems its had or has, there's still a huge asset here and it's not going away," said Ezra Gottheil, an analyst at Technology Business Research.
"It was never the powerhouse people thought it was, and it was never the abject failure people thought it was. It's a young company with a magic formula for generating traffic. It has amazing tech, but its business model is still evolving, and it still makes beginner mistakes," Gottheil added.
Facebook's success has come amid a slew of obstacles.
The company has repeatedly frustrated and angered users with unpopular redesigns, and .
And despite lofty expectations, last summer's initial public offering was lackluster at best, as below its opening price.
Over the last several years, various industry watchers have predicted a massive exodus by Facebook users over any number of privacy or redesign issues. However, the size of the site's user base has continued growing,
The latest milestone comes at an opportune time for the company, which has been facing numerous critical news stories about its flagging stock price.
"It's hard to say whether real success like this will be attributed as real value in the market place," said Shimmin. "But this is absolutely well timed."
Facebook's stock closed at $21.94 on Thursday. That's up slightly from $21.83 at close of trading on Wednesday.
Despite the stock price, the sheer size of its user base gives Facebook something solid to hang its hat -- and its future -- on.
"It's a demonstration of the ubiquity of Facebook," said Gottheil.
"A very large number of people in the world visit it at least once a month. When you eliminate the very young and the disconnected, it's a very high percentage. It's a huge shared experience," Gottheil added.
Sharon Gaudin covers the Internet and Web 2.0, emerging technologies, and desktop and laptop chips for Computerworld. Follow Sharon on Twitter at , send e-mail to or subscribe to .
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