Incoming thought food
Here's how this works.
Yesterday, I received an answer from Excelon, the manufacturers of Stylus Studio, my beloved XML/XSLT IDE, concerning their current lack of OASIS entity catalog support. They said they (at least) knew that is wasn't there, but that I was the first customer actually requesting it.
Strange. I've been using OASIS catalogs since the SGML-era (yup, I'm in this circus for that long), and especially for DTD-guided authoring and validation, I couldn't live without it. And I can't imagine how people working with XML Schema (the horror) or RELAXNG cope with centralized installation and administration of their documentation grammars without them.