First off, I find content aggregators (like DZone) very useful. With that said, I think this technology is in its infancy and have a couple of suggestions that I think would significantly improve any of these sites:
- Provide users 10 or so random stories to vote on. Weigh the entries mostly (not entirely) by these votes. This eliminates both voting up friend's posts and active voters dominating the process. (Stumble Upon does this very well.)
- For each user, find other voters who's votes closely match on stories both have voted on. Very heavily weigh the votes from those matching individuals on new stories when determing what are the top ranked stories for a given user. In other words, I find stories on the Linux core uninteresting and stories on effective programming practices very interesting. So there can be a great post on improving the memory manager in Linux but it still should not show up on the hot list for me.
- Provide markers for users that track the number of users their votes are used to recommend, categories they are a recommend leader on, etc.. This is a measure both of matching and voting regularly enough that the votes are of use. People put in a lot of time to be the 4-square mayor of a coffee shop – provide the same type of acknowledgement here.
- Tie comments back to the original post. If a post gets a robust discussion on both Reddit and DZone, no one on either one sees the comments on the other. Nor are either group tied to the comments on the blog post itself. ID them by source but have two way communication so all sites see the comments from the others.
There's also one other major issue these sites need to address. A lot of them tend to have their content controlled by a small number of people who put in a lot of time on the site. In a sense, we've exchanged the paid editors at a magazine for a self-selected set of editors. It's a wider set of people deciding what goes on the front, but it's not a true wisdom of crowds. At present this limits content aggregators to viewers who's interests match the self-selected editors.
That's it. I'm sure there's lots of other good ideas out there for improving these sites but these are the ones I think would get the most bang for the buck.