There are a ton of feed readers (supporting RSS and Atom), but none are smart enough yet. The best of the best only go as far as to aggregate and display the lot in one merged stream. Others only provide a multi-stream interface.
What I want in the next-gen feed reader is some sort of smart keyword matching system, easy-to-use (and relevant) ranking, Bayesian filtering, similarity grouping (as seen in Google news), a TiVo-like intelligence (maybe going as far as suggesting new feeds it thinks I might like), a timeline widget, and a vFolder-like concept (saved searches) like Evolution has.
It should also be able to weight graphics-heavy posts a bit higher — think comics and photo-blogs. Most reblogged stuff is text-only, so graphic intensive posts would probably be interesting, easy to scan, and most likely original.
Feed readers need to take the next step. I want the reader to tell me what’s cool and what I should look at. I want it to know what I find interesting and tailor my stream of feeds to my constant updating profile.
Having these features would be great and would, as a bonus, save so much time.