Social networking is conquering the Web, and the two leaders in this growing market are Facebook and Twitter. Each site has built communities of millions of users and developers in just a few short years, and they are fighting each other to become the top destination for Web users looking to share information with friends and colleagues.
Facebook, launched in February 2004, lured 135.4 million unique visitors to its site in April 2010 for a whopping 3.2 billion total visits, according to Compete, an analytics firm. Twitter, launched in March 2006, lured 21.5 million unique visitors in April 2010 for 147.4 million total visits.
Facebook is clearly the most popular social networking site, and it trails only Google as the Internet site with the most visitors. If you don't count YouTube, the video sharing service, as a social network, then Twitter is firmly in second place, well ahead of additional rival LinkedIn, a business networking site that had nearly 13 million monthly visitors in April 2010.
Facebook has tried to counter Twitter's rise in various ways. Aside from trying to purchase Twitter in the fall of 2008, Facebook added @tagging in September 2009 and created a "Lite" version that was similar to Twitter, but Facebook shut the "Lite" service down in April 2010 after less than a year.
Most significantly, Facebook has rolled out new privacy settings that make more user content public, and therefore more like Twitter, where content is public by default. However, this strategy has backfired on Facebook, with users complaining that privacy controls are too complicated to understand and actually make it harder to hide personal information from non-friends. Facebook responded in May 2010 with a new set of privacy controls, but it remains to be seen whether this will satisfy wary users.
Twitter hasn't had to deal with the same type of privacy backlash because the company has always made it clear that tweets are intended to be public. Users have the option of "approving" followers, thus preventing most of the public from seeing their tweets, but this is the exception rather than the rule.
Twitter has its own problems. Downtime has frustrated users on many occasions, although this has become less common in 2010. Twitter also can be an effective medium for spreading viruses, particularly with shortened links that hide the original source.
In fact, many types of security threats have plagued both Facebook and Twitter, including stolen accounts, worm attacks, phishing, botnets and spam, leading CIOs to be wary of increasing employee use of the sites.
Despite these security and privacy risks, Facebook and Twitter are undeniably on the rise. These rival sites are attracting attention from competitors, as seen in Google's unveiling of Buzz, which brings Facebook- and Twitter-like status updates to Gmail.
Many Internet users log on to both Facebook and Twitter because of the sites' different strengths and because they want to separate one group of contacts from the other. But Facebook and Twitter executives know that many people simply don't have the time or patience for more than one social networking site, and the battle for market share will only grow more contentious as the financial stakes get higher.
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