{'users': [{'name': 'joe', 'age': '12' }, {'name': 'bob', 'age': '23'}]}
<users><user name='joe' age='12' /><user name='bob' age='23' /></users> {'users': [{'name': 'joe', 'age': '12' }, {'name': 'bob', 'age': '23'}]}
<users><user name='joe' age='12' /><user name='bob' age='23' /></users>{ name: 'joe', dob: { m: 1, d: 2, y: 1934 } }
<user name='joe' dob='...???...'>
<user><name>joe</name><dob><m>1</m><d>2</d><y>1934</y></dob></user>
I actually wasn't trying to make the "XML is bigger" joke because that isn't what's important to me. Structurally XML is harder to use.
{users: [{name: 'joe', age: 12}, {name: 'bob', age: 23}]}
<users><user name='joe' age='12' /><user name='bob' age='23' /></users>