There is a whole cottage industry built around gaming Digg. It was a sweetheart deal, the "news sites" provided top-10 lists, tin-foil-hat opinion articles and short summaries of real news articles on real news sites mixed with a heap of ads. In exchange, Digg would give these sites enough traffic to make a living. Digg just violated the rules of this little deal (via the diggbar) and tried to take more than its fair share. Of course these guys are pissed--they had a deal, blackheart!