FeedFusion

FeedFusion is the next generation RSS Reader designed to take advantage of the newest technologies available to make your RSS reading experience more pleasant.

FeedFusion supports almost any news format available today like RSS 0.9-1, RSS 2.0 and ATOM are already on the list and because of its extensibility, it will allow other formats to be readily supported.
Because you need an easy way to switch from your old RSS reader to FeedFusion the program also supports OPML file import.