Here's a screenshot of my signature:

I had three posts on the same page, they were all like this. What happen?

We know, we're currently working on it. It shall be fixed momentarily.
*closes*

Looks fun, though, doesn't it?

For those who experienced the problem, it was a sort-of upgrade of the spoiler done on the live server (...its a big problem for me). It has since been applied to both spoilers, and allows you to place nearly infinite text in spoiler without page load slow down (so feel free to spam your signatures).

...Next upgrade, AJAX!