This enables .e.g. transformation of org-mode files with latex templates, to html slides or even into .odt files and customization via filters over pandocs AST. These filters can be not only written in haskell but in pretty much any language.
My main use case is exporting scientific manuscripts from org to semi-workable MS Word docs for collaborators to edit. Not sure how merging changes back in is going to go...
When I started writing a static site generator powering my current personal site, I wanted to parse .org files in the generator. I very quickly gave up and decided to manually export my .org posts to HTML, and parse that instead (see [0]). I didn't realize back then that Pandoc can handle .org files; I probably would have decided to shell out to it instead. Then again, if there's one thing I learned writing a static site generator (twice), it's that the next time around, I'll pick up one that's already written by someone else :).
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