chrisnorthwood

Pretty simple, really. Adds a new type of feed you can subscribe to. Simply 
add <code>?feed=json</code> to anywhere you get a normal feed to get it in JSON form 
(but with a cutdown version of events).
Version 1.1 added support for JSONP. To get a JSONP response instead of a 
normal JSON structure, simply add <code>jsonp=callbackName</code> to your query, where 
 callbackName is the name of the function to be wrapped with.
To use this with jQuery, you’ll want to do something like:
<pre><code>$.getJSON("http://example.com/feed/?feed=json&jsonp=?",
 function(data){
 console.debug(data[0].title); // print title of first item to firebug console
 });
});
</code></pre>
(thanks to Dan “Tack” Trudell)

JSON feed

Pretty simple, really. Adds a new type of feed you can subscribe to. Simply

David Shanske

Daniel Jalkut (Red Sweater)

mantonr

Adds a JSON Feed to your WordPress site by adding <code>/feed/json</code> to any URL.
The JSON Feed format is a pragmatic syndication format, like RSS and Atom, but with one big difference: it’s JSON instead of XML. Learn more at <a href="http://jsonfeed.org/" rel="nofollow ugc">jsonfeed.org</a>.

JSON Feed (jsonfeed.org)

This plugin is simple to install, adds no weight to your site, and does what it says on the tin.

JSON feed vs JSON Feed (jsonfeed.org)