Some sort of ML/Bayesian filtering to determine which items are duplicates and know which site I prefer getting my news from (e.g. engadget over slashgear.)

I've been wanting to implement this into Vienna for years now, but time and OBJ-C knowledge has been the main barriers.

Reederapp guy, if you are listening, please add this to Reeder as it really is the perfect interface bar this one feature.