It sounds to me more like the javascript specification has a bug or design flaw, rather than saying as a blanket statement that JSON isn't really part of JS. Ideally, javascript and JS implementations should fix that flaw, rather than parsers having to work around it.
ECMAScript was standardized over ten years ago. The specification has been publicly available and (as far as I know) every implementation has treated line terminators equally. We can't just change 5+ implementations of JS to make it compatible with a some tiny data format that works fine 99% of the time anyway.
I'm not saying that JSON isn't a part of JS; of course it is! I'm just saying that it isn't a strict subset of JS and that you can't depend on eval() doing the right thing.
