So I went ahead and downloaded this. Not entirely sure yet, but it seems to be working well. It's missing a few things that I'm used to with Reeder. Not necessarily bad, just different. And it doesn't need to rely on any backend other than iCloud.
I did connect it up with my Google Reader account briefly to let it import all my feeds. Unlike all the other Reader-replacements, it imported all my STARRED items. Yeah!!! I really hated to lose all of those. It seems to update very quickly. After the import, I actually logged out of my Reader account. I also downloaded the iPhone app and when I read an item on my Mac it showed up as read on the phone very quickly.
I haven't played around with all the options yet, but it seems very customizable (you can change the background/text color for each feed). It lives as a variable-width strip that you can have floating or pinned to the left or right (including multi-monitor).
Possible Cons
1. Didn't import my folders from Google Reader. Not too big of a deal.
2. Only shows feeds within a folder in date order. No choice to show by feed (unless each feed was in its own folder). Not sure how I feel about this one.
3. No option to send to Instapaper, but you can send it to the Safari Reading List.
4. No Readability integration. This was nice with Reeder because you could often get the whole article (for those feeds that only publish snippets) without having to view in a browser. I think I'll miss this one.
I'm going to go cold-turkey with this rather than Reeder for a few days and see how it goes. But I think it will be a good replacement.
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