The subject line in my email caught my eye immediately: "Thursday -- Garbage Social Networks, E-Flex, and More!" I've been playing with Twitter, and I thought, "Yes! I know just what that means!" It turns out I was wrong: the writer really meant social networks for people interested in reducing the volume of their trash. But I think my version is more interesting, because it explains the incredibly rapid devaluation of social networking as a concept. We really have sunk to the level of garbage social networks.The headline was on a posting in AlwaysOn by "mbmccall" who identifies himself as a venture capitalist and is thinking out loud about a "garbage related social net community." The idea of weighing my garbage every day and then chatting about it online makes me faintly nauseous, but I do agree with something he wrote:

This is not an investment idea . . . . I believe that it is becoming increasingly difficult to make horizontal 'social net' sites work. The barriers are too low and there is too much noise."

The success of Friendster and then the megasuccess of MySpace and YouTube has propelled social networking into the dubious role of being a necessary part of every Internet business plan, the equivalent of "do you want fries with that?"

In the last few months I have tried out a score of Web services that are trying to strike it rich by combining social networking and some object that provides a focal point for all the network chatter. NowThen.com, for example, is a social-networking site where the object is cellphone pictures. eSnips.com is a social-networking site where the object is search terms. And let's not forget what may be the grandaddy of them all, LinkedIn.com, where the object you're trading back and forth in the social network is your supposed friendship with others -- which may be a metaphor for the social-networking phenomenon as a whole, and not a nice one, either.

Twitter.com is an example of what social networking has sunk to: It is a Web app that is sort of the Internet equivalent of reality TV -- dumbed-down communication for the text-messaging generation. Yet Twitter got so popular last week that it got almost too slow to use, and the company that runs the site had to announce that it was trying really hard to upgrade its servers.

Having said that, I have to admit that I kind of like Twitter, or the idea of Twitter, at least. It's just that all my friends are real people, not avatars, and when I try to get them interested, they don't get it. "What's this good for?" is the standard response. When I try to explain that it's not good for anything, but it might be fun, I lose them.

This, I think, is why most social networks are garbage social networks. They're time-wasters and time-killers for people who don't have to worry about responsibility. They are adolescence extenders, not productivity enhancers. People like mcmccall probably love them because they're another advertising delivery system for the 18-to-35 set. But I keep wondering, why would advertisers want to reach an audience that spends so much time following "Survivor" and Tila Tequila it can't possibly be earning any money to spend on the advertisers' product?