The other thing I try to call out about org-mode is that there is nothing else that is likely to be around and useful in 20 years.
For example I didn't quite like how org-drill, a spaced repetition extension for org-mode, handled flash-card grouping and drill selection at run-time so I completely customized it with my own group selection interface.
An open ecosystem of human-signal-capture apps will improve security of the future, i.e. events that have not yet happened. The past is already well monitored and recorded. See "The Adjustment Bureau" for exploration of the topic.
If apps use a mature sync protocol (e.g. WebDAV, CalDAV), they can collectively debug interoperability and cross-platform issues related to that protocol, leaving them free to innovate on UX for mass or vertical audiences. Some examples:
http://www.2doapp.com - CalDAV - iOS, Android and Mac
https://www.omnigroup.com/omnifocus - WebDAV - iOS and Mac
http://www.notebooksapp.com - WebDAV - iOS, Mac, Win
You then use something to sync that file tree to any of your devices. I used BTSync for a bit but found it annoying and I now use Google Drive with a GDrive syncing client on my phone so that the mobile-org Android app is always up-to-date.
It's bi-directional and they use a checksum matching scheme and some import tooling that allows you to suck in changes to those index files from other clients.
Combined w/ MobileOrg sync and the MobileOrg app, it serves all of my note-taking needs quite well.
It's much more than dumb text, too, like Evernote. Structured documents with headers, markdown-like formatting, links, fast-capture templates for stray thoughts, an Agenda system (if you want it, you don't need to use it, I do and have it sync w/ my Google Calendar), exportable to HTML and a few other formats (some people even maintain their websites using org-mode).
Keywords for marking entries and a good search system (combined with Helm it's pretty amazing).
Property drawers for entries.
It's a swiss army knife of productivity applications and I use it for note taking, documents, journaling (with automatic GPG encryption of the entry body), my agenda, quick-capture of ideas, tasks, etc... I use it for grocery lists even.