Hah, it's sitting there waiting for several fonts to load from fonts.googleapis.com, but I have my browser set to ignore any font choices set by webpages. Apparently it's just going to leave the dom empty forever.
I checked that last night, actually. A traceroute showed packets winding their way through comcast's network, hitting google's, and then vanishing. Whatever the problem was, it's been fixed. The moral of the story is to never rely on third-party assets, especially for synchronous stylesheets that block the browser from even parsing the rest of the page.