Dave, my standard caveat when putting words in others' mouths: I think this is what you mean but I'm probably wrong and am eager for correction.

First, I think you're assuming that each multiauthor category is on one topic; no sub-categories within a synthetic feed. Correct? So you could create a Books channel from dozens of categories. But if you want to go further, say categorize into Tech, Fiction, and Non-Fiction Books, we will not break this down further for either the authors or the channel editor; entire new categories will need to be created.

A few riffs on the idea.

Inputs.

The default synthetic channel could be automatic; sources just flow through to html and rss. Or...

Some channels require review/approval by the editor before posting, reflecting trust/confidence and signal/noise of each channel. Suggesting the editor needs a place to

• review/approve individual posts,
• manage channels belonging to a composite feed.

Author points

From an author's view, does a push component make sense? (Send this message about this particular book to that Booklist feed, but not all books I post about.)

A 'join' component? Submit an rss feed to an editor who accepts/declines to add it to one or more synthetic feeds? Request to be removed?

Automatic Acknowledgement: Your rss feed has been added to this composite feed and can be seen here and syndicated there.

Outputs.

Embed sources in the descriptions.

New theme types?

Will the composite have its own rss feed out? If so, can these become recursive? If so, can we have some measure of duplicate-post detection?

OPML file describing the elements of the synthetic channel, so it can be passed around like our orange rss files?

Can I choose to have the synth channel active but not to render? This way I can use the collection of sources to group my News Aggregator feeds by topic without rendering them all to rss or html.

The Shifted Librarian >

John Robb >

"This is something I would love to see.  A small town newspaper builds a site with Radio.  It provides Radio to all of the community leaders in town, such as the local fire department, the police, the schools, the community organizations, the local sports teams, the zoning board, etc.  All told it provides 50 licenses, templates, and a location to post ($2k).   It then links to these organizations via its home site and aggregates RSS style news.  It accepts more community weblogs from others that buy the software on their own and begin to publish (my town's girls soccer team has a Radio weblog, through no work done by me)."  

John then goes on to extrapolate this scenario a bit further. I've been toying around with trying to do this for the newly-incorporated village in which I live. My plans aren't as grandiose as John's, but the $5,000 seems doable to me.

The problem is that no one here has $5,000, especially the Library, which is the most likely candidate to start such a community network. And that $5,000 could easily double by the time you take into account hosting (or server installation), training, site design, documentation, and marketing. Unfortunately, no one has that kind of time right now, least of all a volunteer like me.

In addition, the major component that is missing from this scenario is subject access. ...

So while this may work in a larger town with more resources at its disposal, I don't think I'll be able to jumpstart something like this locally. At least, not yet, even though we sorely need it.

Phil > Three things, Shifty:

1. Think Manila (over Radio) for your town. $1000 vs. $5000 for software licenses. Centralized backup. School customizations (blogs and themes for teachers, students, projects) exist. No worries about individual licensing of hundreds of users.
2. Navigation will come. Google is here. And affordable browsing by topic, with automatically created categories, is just a few years' off, imho.  
3. And leave marketing to the other groups in town: Schools, scouts, chamber of commerce. If you have a local cable company (public access?) or ISP, they may also be helpful in getting the word out.