Export to Microsoft Word as alterative output format?

[istathar]

So I don't want to do this; the point of publish is to make beautiful .pdfs. But sometimes you need to get a document into .docx in order to subsequently use the content in someone else's publishing chain.

pandoc supports conversion to Microsoft Word, of course, and very cleverly you can do

$ pandoc -i TreesAreGreat.markdown -o TreesAreGreat.docx --reference-doc=Reference-A4-MicrosoftFonts.docx 

with the reference document containing the appropriate styles for headings etc. Perhaps we should support taking a .book file and concatenation its content into something that Text.Pandoc can write to.