Edit: clarification as HN won't let me reply any more.
That's why there is the distinction between well-formed and valid XML documents. Only with valid XML documents there is a schema attached that will describe these nodes with the type attribute. And because it is extendable, these types can be anything but they will be automatically validated by the parser.
JSON OTOH doesn't have this extensibility. There are a couple of predefined types but if you need to go beyond them (and this happens all the time because JSON doesn't even define a date type!) any interpretation is up to the parsing program and this can vary tremendously (again, look at the handling of dates and for example the questions on stackoverflow about them).
It's just meant to be human readable.
If you want human editable "json", use Yaml: http://www.yaml.org/ (it's a superset of Json that adds comments, linking etc.)
However, I hate YAML with a passion. It is worse than XML in my books. I can usually read JSON fine. I can also read XML in many cases. For the life of me, I just can't read YAML. It has something to do with "-", line indentation and different ways of writing lists.
Of course, someone will say YAML is technically better ...
Could you provide examples? I'm trying to collect more examples for a JSON validator -- http://mattfenwick.github.io/Miscue-js/ (built during a big project using JSON, after I started running into some issues that I couldn't check using other validators)
I'd love to hear more examples if you're willing to share.
