Think about it. Safari can run in the background and periodically check your RSS feeds. There could be a feeds section in the bookmarks section with the number of unread feeds next to it. Also, the icon on the SpringBoard could have a badge on it with the number of total unread RSS feeds. The desktop Safari has it... MobileSafari would be awesome if it had this. The more I think about it, the more it makes sense to me. Safari currently doesn't use a badge for anything, so why not make use of it for RSS.