CBS (NYSE: CBS) and Time Warner (NYSE: TWX) will begin to deliver video clips of some of their premium content on social networks MySpace and Facebook.

Social network users will put the video in their profiles and be allowed to forward it to friends. According to The Wall Street Journal, "As the social-networking sites have grown, so has the competition for viewers and advertisers." The clips will contain advertising as a way for the media companies and social sites to make money.

The effort will amount to another failed attempt to make money off of web distribution of video.

There are now dozens of projects meant to push video over IP to computers. These range from selling full-length feature films, a product already launched by NetFlix (NYSE: NFLX), to putting clips on YouTube. So far, there is no evidence that any of these projects make money now, or ever will.

I participated in a panel discussion at a conference on Saturday with a couple of young, smart, geeky teenagers -- i.e., the absolute center of most marketers' universe. These girls, Iris and Sheena, were the very definition of "early adopter" and "Generation Y" all rolled into one, a tiny yet brilliant focus group on the future of technology, social networking, and the internet.

Someone asked if Iris had a blog, and she said, "I hate to say this, but [pause] MySpace." She and Sheena both related how they checked out their MySpace accounts daily to see if friends had tried to contact them. For the two of them, both from lower-income families and members of under-represented minority groups, their technology lives consisted of homework, their podcasts, and MySpace.

If I were less of an analytical sort, I'd immediately say that MySpace is clearly winning the social networking arena. The site has the teenagers! What's more, it has hours each day of attention from these girls, from my youngest sister, my babysitter -- all of the 13- to 25-year-old demographic, really. But then I thought for an instant more, and I realized that Iris and Sheena were both the perfect example of MySpace's market domination and the reason why Microsoft, AOL, and Google will always win the race for ad dollars.

There's no money in these teenagers' MySpace behavior.