I was doing some testing of the in Google Chrome (Chromium). I sometimes like to use a different browser just to see how things look.
Anyway, I noticed that "menu flyover images" weren't changing in Chrome. But the text (Description and Time) were changing. Odd thing was that ONE of the images changed, but the others didn't.
Still, the fact that it works for ONE image, but not others is odd. Maybe I can investigate when we have some "free time".
Later, I tried to repro this, and found that I couldn't reliably reproduce it.
Chrome also puts each tab into a different process space. I like this because I think it will add stability, but I also think it was done for performance reasons. I think IE 8 also will put different tabs into different processes.
Anyway, Chrome is a different beast and may have odd behaviour until it stabilizes.