This is great news. Via Tim Bray, via Don Box, it turns out Oleg Tkachenko has been able to generate Word documents with WordML.
This is great news to me, first of all because it's good to have an open word-processing format that interoperates fully with Word. Assuming that the interoperability is real, as this would seem to indicate, although this is a very simple example.
But the second and main reason I'm excited about this is the following. One of my long term goals is to never have to write a document in a word processor ever again. I mostly hate the things. I want to be able to type plain StructuredText and transform that to whatever output format I want, whether it's HTML, LaTeX, DocBook, RTF, PDF, or Word. I figured I'd be able to interoperate with Word by writing VBScripts that would use Word's object model, but now I won't have to anymore 
Not that my ST parser is close to finished, but that's the goal anyway.
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