The reason Digg has unblocked the site is because Digg has new spam armor according to TechCrunch.
The reason? Based on a conversation I had with Digg founder Kevin Rose recently, Digg thinks they are winning the war over the problem of "grouping" behavior (where groups of Digg accounts are controlled or effectively controlled by a person or group and can push stories to the home page). The changes they've made to Digg over the last few months, Rose says, allow them to monitor grouping behavior and stop it before it can drive a story to the home page. Thus, there is no real need to ban any particular site from Digg. They are confident that if a story from a previously banned site makes it to the home page, it deserves to be there.
Spam and fake stories are a couple of the biggest problems that social media website face. Sometimes Digg users will quickly point out that a story is a fake to keep people from Digging it. There was a fake story on Digg recently that said Britney Spears has committed suicide. Fortunately, the story did not get very many Diggs because some Digg users quickly pointed that the story was a fraud. This help from users may just as crucial as any new spam fighting algorithms Digg develops.
Pronet Advertising has a 
