As I called out in viewing diffs between powerpoint decks (with a little help from adobe), I'm on a hunt for the ultimate approach to allow multiple folks to edit presentations without having them step on each other's toes and that allows for normal source code control to be applied to the "source" file(s). Using markdown still seems like the best approach, but I still haven't found the perfect solution. Deckset (a Mac-only app) comes pretty darn close.
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