With all the activity around OPML, the editor, the beta of the validator, and the recent release of the community server, I've been steadily getting inquiries about extension mechanisms for OPML. I think it's now a good time to start discussing this.

Basically, I think OPML should have a way to include elements from other namespaces, much as RSS 2.0 does. Developers should, whenever possible, use capabilities that are already in use by others, or included in the core spec, or recommendations or guidelines. I think RSS 2.0 would have done even better if this had been spelled out in the spec, so I plan to include this advice in the new OPML spec.

I think we are at the point where developers should be discussing it openly with others. This should be done with concrete examples of real-world applications, ones that are driven by user needs and economics. OPML should continue to be grounded by practicality and pragmatism.

If you have applications in mind for extending OPML through namespaces, please post a pointer to a page with examples and explanations in the comments below, and if possible, provide a place for developers to comment. Thanks!

# Posted by Dave Winer on 11/17/05; 10:05:52 PM - --