How Facebook took over the Web...

(Credit: Screenshot by Lance Whitney/CNET)

Facebook is on its way to 1 billion users with an IPO around the corner. Not bad for a company with its roots in a Harvard dorm room.

But how did it achieve its grip on the global market? New findings from Nielsen offer a peek into some key milestones for the social network.

Facebook's user base currently numbers more than 900 million. But it's also one of the most visited Web sites in the world, according to Nielsen.

The site received around 152 million unique visits from people in the U.S. in March, which means that more than two out of three online Americans checked out Facebook that month. In such countries as Brazil, Italy, and New Zealand, the rate is even higher.

Facebook first grabbed 10 million unique U.S. visitors in November 2006 and 10 million unique U.K. visitors in April 2008. The site captured 10 million unique visitors in France, Germany, and Spain in 2009, Nielsen said.

In August of last year, Facebook surpassed Orkut as the top social network in Brazil and has continued to grab more users in the country since then. MySpace was also once a hot social network. But in January 2009, Facebook officially surpassed MySpace at the top social network and has held that title since.

Facebook is currently ranked top among all social networking and blog sites in 11 of 12 major countries around the world. The following table from Nielsen shows Facebook's reach in those 12 countries.

(Credit: Nielsen)

Of course, not everyone is a fan of the giant social network.

Half of the 1,000 Americans recently polled by the AP and CNBC believe Facebook is a fad. General Motors revealed this week that it was yanking its advertising on the network because it didn't think the ads were effective.

Concerns have also been raised about the company's move to go public. Half of the people in the AP-CNBC poll think the initial offering price is too high. Many also question whether CEO Mark Zuckerberg has the skills to manage and expand a large publicly-traded company.

And the company has consistently gotten into deep water over privacy issues, angering users and advocacy groups. Only 13 percent of the people polled by AP and CNBC trust Facebook "completely" or "a lot" to keep their personal information private. More than half (59 percent) said they have little or no faith in the company to protect their privacy.

Facebook has made tremendous strides since its birth in 2004. But the company will face more challenges ahead as it strives to grow both as a social network and a public corporation.

(courtesy:cnet.com)