Many commends are (correctly IMO) pointing to JSON as superior to YAML given YAML's problems, but these ignore JSON's problems due to its lack of semantics. When moving JSON between systems, the JSON parser makes certain assumptions about the JSON document, such as whether the numbers represent integers or single-precision or double-precision floats. This is certainly less obnoxious than "no" being treated as a bool, but it is a problem.
A friend of mine created Preserves[0] in part to resolve this problem. I'd encourage everyone to check it out. To be fair, he's also quite pro-Dhall and Nix.