The top menu has moved to the left. I checked in two different browsers.
Sorry about that. I broke this while rolling out support for fixed topbar across all network sites.
There's no graceful way to make this work right now with the custom bar in play as well. Not without a fair amount of effort, at any rate. Since Ask Ubuntu is going to get a new theme soon, I'm deploying a change now to defer fixed topbar support until that time.