Digg is nothing like HN. Granted, they are popular user submitted story sites with comments, but it's about the community. I visited Digg for a few weeks then stopped going because there was frankly lots of crap and trolls on the site. That is not to say that HN doesn't have some bad cookies here and there, but I got fed up with Digg when I saw lots of ignorant comments that were just meant to be hateful rather than for a positive discussion (particularly in the religious domain). HN for the most part, stays on the topic of startup/tech news, and has reasonable discussions.