This site mentions some very interesting reasons for using json.
Reasons for JSON
* JSON is easy. No really. It’s so easy, it’ll make you sick.
* If you’re familiar with writing classes in PHP, then you’ll most definitely be comfortable with writing JavaScript in Object Notation
* JSON is nothing more than name : value pairs assigned within an object.
* JSON is easy to understand because if written well, it’s a self-documenting structure.
* JSON is fast!
* JSON organizes the ugly mess of procedural programming. Imagine having more than one init function.
* You can impress your friends with JSON because it’s pretty looking
* Your co-workers will love you for writing in JSON because it will most likely not conflict with their scripts that are being called within the same web documents.
In additon some sample code is given. This may come in handy as a reference.