This highlights the fundamental problem of social bookmarking/voting sites: the more people that join the site, the lower the common denominator of the content gets. I've seen it happen to Digg and Reddit, and it is bound to happen to Hacker News at some point.  It makes me wish that there could be groups formed within these websites that are kept small, and you would only see stories that are voted on by those members. This would be different than the sub-reddits solution because it would apply to all content, not just a specific category.