CSS Tabs With Submenus

Adam Kalsey recently made his own CSS Tabs with a subnav generated from a nested list. His HTML doesn’t validate yet, but I don’t think that’s too far away. He points out what makes his tabs different and brings up an interesting point: his list markup doesn’t change from page to page. The browser determines the highlighted tab in his list from the body id, not the li id or a id. Is is better to change the ID of the body element before another element? I don’t know. It probably is, but it’s something to think about for those who use lists to generate contextual navigation.