Since it doesn't say on the website, it currently supports Feedbin, Feedly, Feed Wrangler, Feaver, Readability, and a locally stored feed list.<p>Also, here is an article talking about it (and showing images of it), if that's your thing: <a href="http://www.macstories.net/news/reeder-2-for-mac-public-beta-now-available/" rel="nofollow">http://www.macstories.net/news/reeder-2-for-mac-public-beta-...</a>