Randy asked me to deliniate some of the features I would like to see in my syndication feeds/services.  My problem is that as I attempt to scale the number of feeds that I am watching (I am over 100 right now), it is getting difficult to manage.

Here are some features that I would like to see:

1. A synthetic feed editing interface.  An easy way to create a selection of weblogs that combine into a single synthetic feed.  A simple point and click interface that lets me deselect and add feeds to that synthetic feed. 
2. Query based synthetic feeds.  The ability to run a search query against a selection of feeds which creates a synthetic feed.  The ability to do this against Google News would be nice too (I have built feeds based on Google News feeds already, but it is a pain).
3. Blogrolls of synthetic feeds.  The capability to build a simple blogroll of those synthetic feeds (a nice box/list that fits into the weblog format).  Radio has this, but it would be nice to see the feature set improved.  It would also be nice to see something like blogrolling.com for synthetic feeds.
4. Simple ways to share synthetic feeds.  Simple publishing methods either through a service or via a publishing tool.
5. A rating system for synthetic feeds.  This is particularly important for query based synthetic feeds.  I would like to see a darwinian system for the best feeds developed for specfic topics.
6. A packaged way to create "Feedrings" that replace "Webrings."  This would allow me to create or join ad hoc "birds of a feather" syndication rings with other writers.  "Join my technology Feedring" etc.  The mechanism for people to subscribe to these feedrings would be on the front page of all members.
7. Simple hand edited feeds.  A simple system to select the best feed items from a synthetic feed and republish it as a feed.  I know that many weblogs do this already on their main page or in a category.  However, a service that makes these edited feeds easy to share and rate would be nice.  A best of the best feed for a specific topic would be nice for archiving.
8. Feed networks that leverage networks of affiliated individuals.  A system by which ratings on specific feed items flow up to a single combined synthetic feed.  A slashdot approach to finding the best.  I could set my threshold level at three votes within the community of webloggers and not see anything below that.  This could in turn be used to create a group weblog.  This is perfect for a campaign weblog.

This is just off the top of my head.  Some ideas overlap.  Hope this helps. [John Robb's Weblog]