Whether social networks ever take off as advertising platforms will probably be a question answered by the sites' users. But in order to give their users a chance to weigh in, social networks must clear their sites of a common foe -- spam. MySpace, which has suffered more than its share of spam attacks, has won a big victory against one spammer.

Sanford Wallace, who MySpace dubbed a spam king when it filed court papers against him last March, will no longer be able to pester the social network's millions of users. After failing to mount much of a defense or respond to requests for discovery, a federal court in the Central District of California entered a default judgment against Wallace.

It's not yet clear what damages Wallace will be ordered to pay. But according to CNET, Wallace is no stranger to the law. In the past, Wallace and his company, Smartbot.net, were ordered to pay more than $4 million in connection with litigation filed by the Federal Trade Commission, AOL and Concentric Network Corp.