Appears to be generate by client side scripting by the look of it.
It also means that none of the sub-menu items appear in screenreaders (or at least not in Fangs), which isn’t very friendly towards visually impaired users.
Cheers
PAE
This might help for main column menus: http://www.sohtanaka.com/web-design/mega-drop-downs-w-css-jquery/
or a post on here.http://ww.wp.xz.cn/support/topic/making-horizontal-menu-with-twenty-ten-theme?replies=26
As for the on-hover styles in the I WANT TO, some curved borders and changing of background-color wouldn’t be too hard to add once you have to structure set up.