This page is the first time I'm hearing of JSONResume. Honestly, it sounds excessive and only useful for applicant tracking systems (which can be useful if you're in an industry that's ATS-heavy, which mine is not)
The fact that there isn't really any sort of decent open standard is shocking to me. Almost every single person entering adulthood will have professional experience they need to track.
I think I've settled on storing and updating the data in YAML, then building tools to produce JSON in the JSONResume format, HTML in Schema.org, and XML. At least this way it'll be easy to update, and it's the least burdensome path if I have to convert it to another standard later.