Don uncaves. ;-)
Accordingly, I've converted my rss 2.0 feed from <content:encoded> to the to the more bandwidth and xpath friendly <xhtml:body>. It looks like gotdotnet and blogx users will soon follow. Hopefully the owners of the wellformedweb and w3future weblogs will take notice.
The updated feed is valid, and it uses namespaces in exactly the way that rss 2.0 and xhtml intend. I've tested it with radio and syndirella.