I've noticed that all wiki articles don't display correctly. I'm not sure if it's just my system, or if other people experience it. I've attached a picture to illustrate how they appear. I'm running Firefox 3.5.5 in Ubuntu.
I suspect it's limited to that skin. I didn't err... well.. fully test that skin before putting it live. It will work with the other two skins that don't have the left hand menu.