For taking notes you don't need todos or the agenda -- it's heirarchical, fast to search through, and pleasing to the eye (at least, to a similar level to markdown). Aside from that, the syntax is at least as expressive, if not more so because of the extensibility of the language it's written in.

Yes, buying into the todo and agenda systems effectively requires using an external integration script or using emacs all the way through, so that's not all that great. I, too, have yet to figure out how to integrate it into the usual PIM stuff like next loud calendars, etc.

Has anyone else managed to figure this bit out?