Douglas Crockford proposes that loading JSON documents be moved directly into the browser, in much the same way that XMLHttpRequest is. There are many advantages to this (which Crockford outlines) including increased security and the fact that JSON has become the way to load data into the browser for AJAX applications.
We've done similar work here using the SCRIPT tag to do cross site JSON loading. Crockford's proposal would obsolete this (and we'd be happy about it).
You can read the proposal here. Hopefully some bright Firefox and IE gurus will pick up the torch for this one.