Found the solution. The cufon scripts aren't reloading after the ajax call. You need to:
(a) put a reference to jquery above the cufon script references
(b) add an "onResponseEnd" client event to RadAjaxManager
(c) add the onResponseEnd function that loads the cufon scripts and then refreshes after each ajax call
note that the URL is the url where your scripts are on your website.