> The examples are in XML because json is, (and I believe at this point), still not stricly an (accepted) hypermedia capable format, thus not adhering the HATEOAS constraint, and thus cannot be restful. But to be honest, I'd prefer JSON over XML anytime.

What exactly is the criteria of being a "hypermedia capable format"?

The linked website gives an example of how the response on a bank-account like API might include links to other actions; XML and JSON seem equally capable here, as they can both encode links.

He mentions on another page,

> Unfortunately, JSON is not a hypermedia format. There is no predefined way to deal with link discovery in JSON.

Is there a predefined way to deal with it in XML? In the earlier example, I had assumed he did exactly what you would do in JSON: make up a field for the purpose.

Though, honestly, that would seem to be the purpose of the "Link:" header.