Paul Schaeflein has written an article about reading and writing RSS with SharePoint. There are many examples on RSS with SharePoint, but Paul gives a good overview on how to deal with it. So, a worth reading!

“A popular request for intranets is inclusion of current news or sports headlines. Microsoft addressed this request in its Online Web Part gallery with some Web Parts that display content from MSN. These Web Parts provide the basics from a single provider. On today's Internet, there are many other choices for information. This month, I will review a few different solutions for including part of this vast information on a SharePoint site.
Syndication technology has grown very popular over the last year or so. This technology is called RSS, and it allows content publishers and consumers to exchange information very simply. At its core, RSS is an XML file that follows a specific schema. A publisher produces an "RSS feed" and makes it available at a location (URL). Consumers (which are usually computer programs) read the feed via the internet and re-format the information for display. Since SharePoint understands XML, it is well suited to process RSS. RSS on the internet
RSS is used in many places on the internet. Major news publishers (The New York Times, CNN, USA Today) provide RSS Feeds. The primary Web portals (My Yahoo!, My MSN and Google's Internet Gateway) allow visitors to add RSS Feeds to their personalized home page. There are also many Windows (and Mac) programs that consume RSS Feeds. These programs, called aggregators, are also being merged into forthcoming versions of internet browsers.”
Read complete article