Steve Minutillo has posted about the development status of Feed on Feeds:

You’re both right, FoF has been dormant for a while. It’s about to come back to life. I’ve got a minor update ready to release, but I’m going away on a vacation for a few weeks, and I don’t want to release now in case there are show-stopping bugs. But I will release it as soon as I’m back.

I’ve thrown out the implementation of categories that I mentioned previously. It was based on a hierarchical tree structure of categories, which I’ve since decided is the wrong way to go. Things like gmail, flickr, and del.icio.us have convinced me that tags are the way to go. An implementation of this, as well as multi-user, are next on my priority list, as well as continuing the clean up and seperation of “engine” from “display” to make FoF even more hackable.

Works for me. As itch-scratch-ware, I’m always willing to wait.