Atom Schemata
Tim Bray: Here is draft schemaware for snapshot 0.2 of PEAW
In the process, Tim generated a lot of feedback.
Meanwhile, a few days ago Sean Palmer initiated an ExtensibilityFramework that just so happens to address a number of Tim's issues. In the process, a RelaxNG grammar was produced which covers not only the core elements, but also all extensions.
The purpose of this extensibility framework is to allow a uniform mechanism for handing text (with and without markup) and detecting URIs. The latter would also help with things like xml:base processing.
Sean produced a Python/SAX parser that converts this into RDF N3. Sjoerd Visscher produced an XSLT transform that converts the same input into RDF/XML.