In my opinion, NewsGator is the best RSS aggregator. It's integration with Outlook makes reading feeds ultra-convenient. If you haven’t tried NewsGator now’s the time because version 2.5 has been released. I’ve been using the beta and the integration with the NewsGator Web Edition is fantastic. Works as advertised. You might also want to try their podcasting application FeedStation. It’s not better than Doppler, yet. But I have a feeling it’s going to get there.