Was stoked to see this worked like a champ in Chrome. I was actually going to completely rip out the website navigation bar in TwentyEleven and use it for a Disjointed List type navigation of my site.
Unfortunately, doesn't work in Firefox. Can't click on the links on the navigation for whatever reason. It's accepting the clicks but the AJAX page/content() swap is not workin'.
This is Gecko vs. Webkit as far as I know, may be a good place to start!