I posted a short note about Radio 9 developement.
Dave Winer's Instant Outliner
It looks like Dave is porting the instant outliner code in Radio UserLand to his new program called OPML. The dialog box he links to in that post configures the same preferences in Radio UserLand, the program he created over three years ago.
I did some snooping, using the clues that Dave left us all. He's writing a a tool that will ship with the open source Frontier code, maybe even with some new UI elements.
His outline is here:
http://hosting.opml.org/dave/instantOutliner/daveWiner.opml
Subscription in Radio UserLand instructions:
http://radio.outliners.com/outlinerSubMenu
Prefs in Radio UserLand to do this yourself: