I'm having a problem with submenus disappearing (they appear but disappear once your cursor gets near it). This only happens in the first submenu in a menu bar, so if there's more than one submenu, the rest shows up properly.
Some skins do appear to work: None, Custom CSS, Color Scheme, Simple White, WordPress Default and the Flickr theme.
I've tried this in both Firefox and Chrome.
I hope there's a fix for this, because I use the Nvidia skin for my site. :)