Michael Arrington has a good review of MySpace’s MyAd’s platform. It looks pretty smart: display ads sold on a cost-per-click basis that can be targeted based on 1200 categories of users MySpace has developed based on user behavior on the site. As Arrington mentions, if you are looking for California women between 25-30 who like motorcycles—and who isn’t—MySpace has them waiting for you.

Ads are prioritized like search ads based on bidded CPC and click-through rates and the advertiser can set a budget. Will this be a money machine like AdWords was for Google? Probably not: it is limited to the MySpace community and can’t really deal with the apparent lack of engagement that social networkers have for ads. But it will keep the lights on and that’s not such a bad thing these days.

Social networking sites ares still struggling to find ways to make money from the millions of users who swear by this new technology. It is looking increasingly unlikely that these sites are going to print money like Google has done with search and Microsoft did with Windows. They may have to content themselves with just being regular businesses that get enough revenue in to cover costs and deliver a decent return to investors.