Digg's success hasn't come from nothing. The site has overcome failed partnerships, buyout rumors and companies attempting to use its system for their own advantage. Those obstacles have not dented Digg's mounting popularity, and it should be around for years to come. The site is nearing profitability, its traffic has nearly doubled since August 2008, and it reportedly sees click-through rates up to 100 times more than standard display advertising.
For more information on what Digg has accomplished, take a look at TechRadar's brief history of the site.