Using this title Kurt Cagle writes:

"I'd like to push a proposal to both the XML and AJAX communities, something that I think needs to be taken up by the W3C, the OpenAJAX alliance and JSON.org especially. Establish a set of conventions within JSON that most readily facilitate JSON being used in an XML context. These conventions should be syntactical, things that can be done with hash key naming conventions that can be picked up by a JSON/XML bridge to transform between the two formats."

Hmm...  here's what I have to say:

Kurt, this was quietly done some time ago. Just have a look at my blog ("Transforming JSON"). M.David. Peterson has a nice web-service based example, which in real time gets the XML out of the JSON produced by the Yahoo's Traffic Service.

This example just uses the JSON to XML convertor provided by FXSL -- that is the function f:json-document(), written in pure XSLT.

So, no conventions are necessary for transforming JSON to XML !