Called Mash, Yahoo's social-networking site is still being tested (people join by invitation only right now), the Times Online in London reports. "Mash has already been dubbed 'an homage to Facebook' – but with a difference: users of the new Yahoo site can edit each other’s profiles." As a New York Times blog puts it, "Think the Wikipedia version of a social network." Now there's a scary thought. But, as with Wikipedia, changes can be changed back, and the profile owner has the controls: "If you don’t like this game at all, you can change settings to allow just people marked as best friends or family to edit your profile, or you can keep the crayon box entirely to yourself," the New York Times blogger adds. Here are some interesting UK social-networking numbers cited by the Times of London: "One in four UK people with an Internet connection at home now uses a social networking site – rising to nearly a third among 15 to 24-year-olds." And here's Reuters on Mash.