Seems to me that 99% of AJAX is learning to create/use one new JavaScript object along with a bit of fairly standard JavaScript to output the results returned from the server. In fact, it seems that most of the "AJAX" I see being used (including stuff I do) is really just "AJ" (no "and XML" involved in it). Inasmuch as I'd hate to see this site get bloated with too many more forums, maybe you could just rename the "ClientSide Technologies" forum to something like "Client-Side: JavaScript, AJAX, HTML, etc."
PS: I might be inclined to move the "Dicussion" forum group down below the following 2 groups in order to give those more technical groups greater visibility.