It's a closed shop. SEOmoz estimates that the top 100 Digg users are responsible for more than half of the content that reaches the Digg front page. Furthermore

It's a closed shop. SEOmoz estimates that the top 100 Digg users are responsible for more than half of the content that reaches the Digg front page. Furthermore, there could be as few as 20 'superusers' who are responsible for submitting 25 per cent of Digg's front-page stories. If you do the maths, you'll realise that anyone could set up a company with that many employees and have a far more interesting and diverse front page. The title of the article is in definite candidacy for troll-bait, but the above quote is quite interesting. I think the next successful social news dispersion site will be one that figures out how to eliminate that "cliquish" nature of such sites as digg, reddit, et. al. in order to really clear away the fluff.