@druskus Not by much, many YAML *parsers* are crap, but the spec itself is actually designed to be a superset of JSON and doesn't *add* many cases. One example would be that it does the usual unix bullshit of treating 0123 as an octal number... I'm no fan of YAML, but in itself it really doesn't deserve the hate.
@druskus And many of the things it adds would actually allow you to be far more strict, "Tags" are actually a way to express data-types concisely in-band, with JSON you *need* external schemas for that. Problem is: YAML is so simple that people don't read the spec and thus don't use these features...