Scott Lawton wrote:

...

If I put up plain text, I want the plain text to follow some regularization rules, and ZML is the only game in town actively working with etexts (as far as I know at least -- I do recall two other text regularization schemas, but don't know if the authors are doing anything with them.)

There are several schemes in active use, including:

wiki markup: http://en.wikipedia.org/wiki/Wiki_markup

STX: http://www.zope.org/Members/jim/StructuredTextWiki/FrontPage (Structured Text) by Jim Fulton, e.g. for Zope and ZWiki

reStructuredText: http://docutils.sourceforge.net/rst.html for Python's DocUtils

Markdown: http://daringfireball.net/projects/markdown/ by John Gruber of Daring Fireball

Thanks! Markdown is especially interesting since it produces regularized plain text which looks and reads the most like PG plain text, other than Bowerbird's ZML. It's also interesting that there's another ZML in use, so Bowerbird may need to change the acronym he is using for his regularized plain text schema, such as to ZenML: http://rx4rdf.liminalzone.org/RhizML

(I'm not sure if any are being used for the same type of etexts as PG, but it seems likely that the overall level and diversity of activity and tools are more important. e.g. I think all of the above include source code, typically using a friendly "attribution" license.)

My own approach (from 1995) plus links to several others is here: No-Tags Markup: http://prefab.com/ssl/notagsmarkup.html

Very useful information. Thanks. Jon