I think I figured it out. There's an extra comma at the end of a list in the code somewhere that all modern browsers process without error. I bet you have "compatibility view" enabled. Starting with IE8, Microsoft decided that it should allow you to enter a mode in the browser that intentionally re-introduces all of the horrible bugs of previous versions of IE, plus a few more just for good measure. We we refer to it with hatred as "incompatibility view".
Try clicking this icon next to the address bar: http://services.lexblog.com/files/2013/05/ie8_compatibility.jpg
(BTW - why is the IMG bbcode tag disabled now? I wanted to embed the above URL as an image in this post)
I'll fix the root cause of this bug sometime soon and also add something that will attempt to force IE to avoid "compatibility view" by default, but unfortunately, I do not have absolute control over this. No matter what I do, it's still possible for you or a system admin to configure IE settings that will make IE use "compatibility view", or even emulate a prior version of IE (which introduces new bugs as well that didn't really exist in prior versions). It's a big mess that I absolutely hate and makes me want to drop a nuke on Microsoft.