YA3PDNA
Looks like we have Yet Another Three Paned .Net Aggregator.
This aggregator does allow you to have multiple collections of feeds, sorts, searches, and filters your subscriptions by date and content. Sweet. I would personally prefer that this be done over the content than the name of the blog, but what is provided is still quite useful.
I was also intrigued by the way it handled invalid feeds. It colored the icon in red, provided information on what was wrong with the feed, and provided a link to the RSS validator. Way cool!
One feed that it did not like was Mark Baker's, which fails to validate as it is not well formed XML. Another feed it didn't like was Aaron Swartz's, which I will assert is valid RSS. I attribute this difference of opinion to the validator being around longer as I very much recall when the validator choked on the foaf info in the dc:creator element.