I\'m trying to do some jQuery ajax and it works in Firfox and Chrome, but not in internet explorer 9.
The final code will have to go across sub-domains, and this doe
On the http://services.whygo.net/sendAjax2.html page, I see that you've got the expected dataType of the AJAX response coming back from the server as JSON, but the response actually comes back as a plain text string ("Email successfully sent.").  
Perhaps you could try commenting out dataType and let jQuery figure out what type of response comes back.