My favorite RSS client for OS X, Reeder, is available today in Public Beta 3. It's available for anyone to download but keep in mind it is a beta and has some missing functionality. Some of the new key features include:

More themes
Updated UI - OS X Yosemite
Unread and starred counts for smart folders
Private browsing support

Reeder supports Feedbin, Feedly, Feed Wrangler, FeedHQ, Newsblur, The Old Reader, and a whole lot more. Check out the full list of new features here along with a download link.