JSON's minimalism does have some appeal. All you will ever have to deal with are null, booleans, doubles, strings, arrays, and maps. With XML, you can start wit

JSON's minimalism does have some appeal. All you will ever have to deal with are null, booleans, doubles, strings, arrays, and maps. With XML, you can start with an equally simple RPC format but get pressured into dealing with recurring elements, attributes, whitespace normalization, mixed content, processing instructions, and general entity references, just because they exist as possibilities and (most) parsers support them all.