Quarter of businesses surveyed block social networking sites

One in four businesses block access to Facebook, social networking sites – Network World

Nearly one in four businesses block employee access to social networking Web sites such as Facebook and MySpace,according to a survey of about 200 human resources professionals.

With the number of Americans using social networking sites tripling in recent years, use of such sites has grown during work hours. People ages 35 and older are using MySpace and Facebook in droves.