The number of minutes Americans spent on social networking sites nearly doubled in the past year with Facebook and Twitter enjoying explosive growth, according to a new study.
Nielsen Online found that the number of minutes Americans spent on social networks such as Facebook, MySpace, Blogger, Tagged, Twitter and LinkedIn grew 83 percent from April 2008 to April of this year.
It said the total minutes spent on Facebook increased nearly 700 percent year-over-year, from 1.7 billion in April 2008 to 13.9 billion in April 2009.
Facebook was the top social networking site when ranked by total minutes for the month followed by MySpace, which saw its total minutes decline from 7.3 billion in April 2008 to 5.0 billion in April 2009. Blogger, Tagged and Twitter were next.
The number of minutes spent on micro-blogging service Twitter skyrocketed from 7.9 million in April 2008 to 300 million in April 2009, Nielsen said.
"We have seen some very exciting growth in Facebook during the past year, and a subsequent decline in MySpace," said Jon Gibs, vice president, media and agency insights at Nielsen Online.
"Twitter has come on the scene in an explosive way perhaps changing the outlook for the entire space," he said.
The number of minutes spent on MySpace may have dropped but Nielsen Online said it remained the number one social network when it came to viewing online video.
MySpace visitors spent 384 million minutes viewing video in April, an average of 38.8 minutes per viewer, while Facebook visitors spent only 113.5 million minutes viewing video, an average of 11.2 minutes per viewer.
Gibs warned that Web users are notoriously fickle.
"The one thing that is clear about social networking is that regardless of how fast a site is growing, or a how big it is, it can quickly fall out of favor with consumers," he said.
"Remember Friendster? Remember when MySpace was an unbeatable force? Neither Facebook nor Twitter are immune.
"Consumers have shown that they are willing to pick up their networks and move them to another platform, seemingly at a moment's notice," Gibs said.
Facebook recently signed up its 200 millionth member but unlike other Web giants such as Amazon, eBay, Google and Yahoo!, it has yet to prove how it is going to translate traffic into cash.
A Russian Internet company invested 200 million dollars in Facebook last month in a deal that values the social networking giant at 10 billion dollars.