Perhaps GameDev.net should put a message across the top of the site saying, "We just updated our site software. If you are experiencing any problems, first try clearing your cache; if the problem persists, report it [here]"
I imagine quite a bit of people are experiencing the problem and don't know why.
[Edit:] Currently it says, "Ctrl+R your browser". Refreshing the webpage (Ctrl+R) won't fix it: clearing your cache does.