Bad news, it doesn't work in (my) IE 9 as well. It should not have anything to do with Drupal. I've had problems with minified css/javascript and Typekit, but I can see you havn't compressed anything.
I see you are calling typekit as the last script in head. Try move it to the top. And use the advanced embed code instead. I would prefer to use a regular font-face declaration, but Typekit does not support this.