Outline Markup Language (OML), an XML dialect for outlines:
I ... detected a need among OPML users for something more generic, more conventional in its use of XML, and less Userland specific. When I say Userland specific, I refer to the elements that are called out in the <head> element of the OPML spec. There are many applications that will never use these (especially on the web) so it seems better to me to make these instances of <metadata>.
Though I like OPML, I can see why some people would prefer a more formal dialect that can be validated against a DTD. I was amazed to see that OML adopts an aspect of OPML that XML gurus have criticized: the placement of outline item text within an attribute instead of an element.
Because there's no limit on the length of that text, this supposedly breaks XML software that isn't prepared to deal with extremely long attribute values.
Also, the plan to finalize OML by May 23 seems hasty for what's being billed as a community effort. There ought to be more time for people to find out about the project and contribute to its development before it's frozen.