The Markdown toolset seems to only improve as it's capabilities mature. The latest is an "open source Knowledgebase platform that uses static Markdown files to power your Knowledgebase."
http://raneto.com/
I hope very much that Markdown analysis tools come to rival and even best Word's own not-that-great Track Changes feature. Or at least the Confluence tool's change tracking system.
For fans of Markdown [Raneto: NodeJS note manager]
Re: For fans of Markdown
I'm one of the fans and this looks very cool. 
http://raneto.com/ wrote:Raneto is an open source Knowledgebase platform that uses static Markdown files to power your Knowledgebase.