Great stuff. JSON is well on its way to replacing XML for one simple reason - you can access the data from anywhere. This is not the case with XML web services for example. That nice asmx service that works fine on your local machine will not work for people who want to consume the data from another domain. This is what the same-origin policy ( ) is all about. Yes, it works in compiled languages like C# but a pure Javascript/jQuery solution will not work, unless you use JSON.