Making RSS clients, or RSS news/feed aggregator, seems to be a kind of boon in open source community. There are bunch of different RSS clients for the Windows, the Linux and the Mac.
However you can find some common ground among those.
However many of them are not well designed. For example, some are not intuitive, some are hard to add and manage RSS feeds.
Some have wierd screen organization. For example, probably it was introduced by the Outlook, the 3 column view for RSS feeds look awkward and it is not really use the screen estate efficiently.
I prefer the good-and-old style, where you can see the list of items on the left side, article headings on the upper-right side, and its content on the down-right side.
Some doesn’t support multiple languages, and some doesn’t support XML very well.
On the Windows, I would like to give the winner to the RSS Bandit. It is very convenient to manage feeds, has very comfortable. The automatic update of feeds is quite dependable.
On the Mac, the NewsFire provide very clean interface. It once had some problems with newspaper site’s RSS feeds in Korea, but with the latest version, the problem seems to be solved.
Unlike other RSS clients on Windows, its righ pane reflects an articles content when you click an item of a RSS feed. In other words, when you click one RSS feed, the right pane shows available article headers on the right pane. When you click one of them, the right pane is replaced by the chosen article. There is prev\next button on the top. So, it is easy to navigate, or you can always go back to the whole list.
It is very clean UI and very light-weighted program. This is my favourite RSS client program among many Windows/Linux/Mac RSS clients.