Some of the previous discussions about org-mode:
https://news.ycombinator.com/item?id=2423276
https://news.ycombinator.com/item?id=8668271
https://news.ycombinator.com/item?id=2091850
From org-mode website: Org mode is for keeping notes, maintaining TODO lists, planning projects, and authoring documents with a fast and effective plain-text system.
http://orgmode.org/