I use WatiN for integration tests on a site that makes use of AJAX using jQuery. I need to be able to easily wait for all AJAX responses to return after, for example, clicking a button.
My current way to do that is to extend IE and override WaitForComplete and eval some javascript so I know whether there are any pending requests:
class JQueryAwareIE : IE
{...
2009-11-10 14:51:58 UTC in WatiN