I am sure you have had this come up on the forum before, but i couldnt find anything in a search. From my research this is a common IE bug – where text in a certain area (usually associated with floats) disappears until (in my case) a link is rolled over when it re-appears.
I cant really give a link in this case as its all local… Hopefully there are a couple of things i should check right off the bat with this kind of issue!