NewsBlur has been great, but one major thing missing from Google Reader (at least as far as I’ve been able to find) is the old ‘Trends’ statistics. It was useful to be able to see how much there has been from different feeds. And the ‘Longest since last update’ list of feeds was a handy way to diagnose problems.
Discovery is a major v3 feature. dev.newsblur.com is my v2.
I like the idea of showing feeds ordered by last update. I’ll add that to my Organizer feature.