Think again. The menu is broken because they say
(Wrapped and tabbed slightly for readability)
Now, I have never heard of the HTMLElement.currentStyle property and neither has Opera. This causes an error that stops the script. Turns out it is an IE only extension (the standard way is to use the getComputedStyle() function).
Now, it would be so simple, elegant and future-proof to replace the browser sniffer
with a cleaner object detection:
Translation: rather than saying "if this browser is IE" you can say "if this browser knows about currentStyle". Well, that is apparently not 1999 enough for the coders at MSNBC..