Facebook, Twitter say social is the new normal

The social networking phenomenon has nowhere to go but up as computer use becomes more mobile, according to leading figures in the development of the popular sites Facebook and Twitter.

"Two to five years from now, the whole question of what other social networks you use will be moot, because it will all be social," Chris Hughes, co-founder of Facebook, said. "Social is becoming the frame, the filter to a lot of information," Hughes, 27, said. Facebook has over 500 million active users, including more than 150 million who access the site through their mobile devices. The number of registered Twitter users is estimated at more than 165 million. Both companies are privately held, and investors are on constant alert for any sign either will go public. Biz Stone, co-founder of Twitter, said the expansion of social networking would closely track a rise in personal mobility as devices such as smart phones replace traditional computers.