I think that sites like originalsignal and popurls prove that social news sites still have areas to improve, especially with regard to ui design and functionality. In particular, I like the way the originalsignal for digg shows top recent new, top news today, and top news this week on a single page. Additionally, they display multiple categories of content on a single page. Netscape is sort of onto this by using their right nav for other topics.

I think next step for originalsignals is to:
* aggregate posts from across services, normalize the votes, and blend the content
* allow users to make a customized homepage (select topics, organize, insert rss feeds, etc.)
* provide an rss feed

One possible concern though: the use of trademarked names, like the digg.originalsignal.com page. That’s why I think it’s better for them to pursue the route above.