Looks nice a few bugs when trying out with IE 10 though. Filters at the top don't work. Also a way to scope down to only a single RSS source would be nice.
Also, it is possible to view the feed for a single source: clicking on a feed label in the subscriptions list shows just the items from that feed. If you have folders (like there are on the "try" page), clicking on the folder label shows items from all feeds inside the folder, but clicking on the folder icon expands the folder.