I think you've done a really nice job with this. I've already replaced my nytimes.com bookmark with skimmer. One small request - could you put friendly time stamps on the articles, i.e. "posted 3 hours ago" "posted 2 days ago" and/or mark articles that have been read somehow? would just make it much easier to scan the page and look for unread stuff on return visits within close proximity to each other.
I just want to note that if you use friendly timestamps ("posted 3 hours ago"), you take a big responsibility of having them _always_ be correct in any situation and automatically update without reloading the page, etc. They also need to index to Google properly, in a non-friendly format.
