Well, the world didn't end.
By smashing together lead ions, far larger and heavier than the protons used so far, the Large Hadron Collider created a miniature (WAY, WAY miniature) version of the Big Bang (the creation event, not the wonderful TV show). Temperatures were described as "a million times hotter than the center of the sun" (or around ten trillion degrees C: and, no, "trillion" is not a misprint). It's one more big step on the way to understanding the most basic questions about the makeup and origin of the universe. Well done, folks.