This is the philosophy of XML, and it works great. It allows you to put data in a file that's for a specific kind of app. Others wouldn't understand it, which is OK cause they ignore what they don't understand.
It also allows you to use the web to bootstrap something new that runs above the web. Where the web is the gateway that gets you in. When you see the door, many people won't get it. But that's okay if they remember the rule.