[hahamrfunnyguy]

That, not too mention how often do you actually write data files by hand? Maybe a small sample file for testing, but beyond that all data is going to be read in from files or come from an API.

JSON is not bad to write by hand. Simple XML isn't too bad either, but I still prefer JSON.

[hiyer]

JSON doesn't have comments. If I want to know why a config has a particular value, I can write a comment to explain it in YAML or xml, just like I would do in code. Lack of comments is the primary reason I would not use json for anything that needs to be written or read by humans.

[iainmerrick]

This discussion seems to be largely about configuration files. Those usually are written and maintained by hand.