Facebook dominates the social networking landscape by most metrics, such as overall users and time spent per month per user. But other companies, such as Twitter, LinkedIn (LNKD) and Tumblr, are growing faster.
Facebook has 901 million users worldwide, with 526 million described as active daily users, according to an April 23 filing with the Securities and Exchange Commission. The network receives 3.2 billion comments per day and 300 million new photos daily, the company said in a filing for its pending initial public offering. Facebook plans to go public in May.
he second most popular social network is microblogging service Twitter, which has more than 560 million registered users, according to Twopcharts.com. Of those, only 140 million are active users, Twitter says.
LinkedIn is the world's largest professional network, with more than 150 million members in over 200 countries and territories. As of the end of 2011, professionals were signing up to join LinkedIn at a rate faster than two members per second.
Data from Web analytics company Compete show that social networking upstarts such as Google's (GOOG) Google+ service, launched last September, as well as Pinterest and Tumblr, are showing heady growth.
Google+ had nearly 22 million unique U.S. visitors in March, putting it in fourth place behind Facebook (170 million), Twitter (42 million) and LinkedIn (28 million), according to Compete.
Visitors to Google+ grew 14% from February compared with 1.8% growth for Facebook, 13% for Twitter and 7% for LinkedIn.
On a year-over-year basis, U.S. visitors to photo-sharing site Pinterest are up about 4,900%, followed by social blogging service Tumblr at 67% and LinkedIn at 61%.
Facebook rules them all when it comes to user engagement. A study by ComScore determined that each user spent 405 minutes in January on Facebook. Pinterest and Tumblr were second with 89 minutes each.
Twitter users spent an average of 21 minutes that month on the service, and LinkedIn followed with 17 minutes. Google+ brought up the rear with a lowly three minutes in the first month of 2012.