Social media sites such as Digg and Reddit. Not that they haven't already had problems, but those have been largely generated from within, such as the cases where a small clique of Digg users mutually admiring each others' submitted links created an echo chamber of approval for particular themes.

Last week Kevin Rose, the founder of Digg, posted on the Digg blog that to prevent people gaming the system, "a key update is coming soon. This algorithm update will look at the unique digging diversity of the individuals digging the story. Users that follow a gaming pattern will have less promotion weight." But now, those who make money by getting people to come to sites - the "search engine optimisers" (SEOs) - have started to work their particular brand of magic on "social" sites such as MySpace and, of course Digg, and its siblings.

"Somewhere on Digg, Newsvine and almost every other user generated content site out there is some policy about "not submitting your own stories, websites or blog postings", comments "Gray Wolf" (at wolf-howl.com). "Well I see those kind of things kind of like handicaps in sports, they make the rest of kids think they can run with the big dogs, and just don't apply to me. So what if I happen to be mildly schizophrenic, and have lots of imaginary friends who are very net savvy? Are you going to discriminate against the people who are reality challenged?"

In other words, a skilled SEO can create plenty of "people" who will Digg a particular link or story that will lead readers to a site that pays the SEO per advert shown or clicked or, even better, per visitor. "Web 2.0 opens up a whole new game for those creative enough to use to use it," notes Gray Wolf.

Back to Rose: "In the end Digg is yours to control," he wrote. "No matter which stories are promoted, it's up to the masses to digg or bury them. If you see content you disagree with - bury it. If enough people do the same, the system will automatically remove the story." Bear in mind that spam now makes up most of the comments posted on blogs and most of the email that's sent. Now, do you want to bet with Rose or Gray Wolf?

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