What do we mean by that? Hasn't JavaScript always had native JSON support since whenever "eval()" was included?
I think applecore's comment was tongue-in-cheek considering JSON is JavaScript Object Notation and was originally derived from JavaScript.
eval() isn't quite the same. It's unsafe for starters: it permits any JS code, not just JSON.
But JavaScript has the JSON object offering a high-quality, high-performance parser (JSON.parse) and serialiser (JSON.stringify).
Its funny how JSON emerged as subset of JavaScript - easy to parse with eval(). But now if you do that its terrible code. So the subset aspect is totally irrelevant now.
The subset aspect is indeed still relevant. JSONP callbacks[0] make use of JSON's just-JavaScript nature.