Is the Windows 2009/Avalon XAML Format Extensible or Versionable?

Hello,

  I just stumbled over an article by Dare Obasanjo -
Microsoft's .NET XML tech lead - titled "Designing
Extensible, Versionable XML Formats".

  Dare writes:

  An XML vocabulary should be designed in such a way
that the applications that process it do not break
when it is inevitably changed.

  ...

  Why XML formats should be designed to be extensible.

  The primary benefit of allowing extensibility in a
format is that it enables a format to evolve without
requiring central control of the format. A secondary
benefit is that it allows the format to stay focused
and simple by pushing specialized or niche-use cases
and complex solutions into optionally supported
extensions.    

   More @
http://www.xml.com/pub/a/2004/07/21/design.html
     and
http://www.xml.com/lpt/a/2004/07/21/design.html

   What's your take on it? Do you think the Windows
2009/Avalon XAML format is extensible or versionable
or do you think that the Windows 2009/Avalon XAML
format is bound so tightly to the Windows 2009/Avalon
API that it's not really a free-standing extensible
and versionable XML format but just a XML dump. Any
thoughts? Any comments?

   - Gerald

-------------------
Gerald Bauer

XUL Alliance | http://xul.sourceforge.net  
United XAML  | http://xaml.sourceforge.net

Interested in hiring Gerald Bauer? Yes, I'm available.

If you know of an opportunity in Toronto or Vancouver,
please contact me today.


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