Just as a follow up, here's an example of what I DON'T like happening and why I think a Digg listing should be listed below the original content.
Very often diggers repost all of the original content in the comment section of the digg listing "in case the site goes down."
For example, look at this digg listing :
http://digg.com/tech_news/Top_10_Google_Myths
The original content is basically plagiarized by a commenter and if someone comes to that page before they go to the original content source, they likely won't continue on to the actual article.