I\'ve tried to get some content from Wikipedia as JSON:
$.getJSON(\"http://en.wikipedia.org/w/api.php?action=query&prop=revisions&rvprop=content&
You'll need to use getJSONP if your getting data from another domain, it's part of the "same origin policy".
EDIT
Actually what Nick said, slap &callback=? on the end of your query string to invoke getJSONP.
&callback=?
getJSONP