I have spent the majority of my development time over the past few years trying to get IE to play nice with cool things we’re trying to do on the CMS. Not a fun task.
One issue I came across recently pertained to the auto-expand call for iframes on an IE9 page. When you would hover anywhere it would start to resize the iframe automatically. So wonky. And yes, that’s a technical term.
Looked around and found this to be a good working solution when it comes to 1) detecting IE and 2) rendering a different value accordingly.