Wim De Cleen has a great two-part walkthrough up on how to use the new Microsoft Feeds API to display a folder-style list of RSS feeds in Windows Forms. The Feeds API is new with Internet Explorer 7, and is the programmatic interface to the new Windows RSS Platform.

I'm working on a white paper that details several ways to consume RSS inside of a Windows Forms application, which will include a section on the Windows RSS Platform. Building a feed reader app well is difficult, as you have to account for users (like, um, me) who have dozens or hundreds of feeds. Updating these in near-real-time without pegging your processor and absorbing all of your client's bandwidth is a challenge. The RSS Platform makes it easier for developers to build RSS-powered apps by handling all of the scheduling, throttling, and storage issues on their behalf.

De Cleen's example is what is traditionally called a "folder" approach to viewing feeds: view one feed and its contents at a time. I'm working on a sample that takes a "river of news" approach, displaying all unread items sorted by date. I'll post it here when it's complete, and include a pointer to the published white paper when it's ready.