In looking at Firebug I see:
SCRIPT1015: Unterminated string constant full.js?v=a56a3c2dc16e, line 63 character 148
If I use Firefox, things work fine. If I go to Meta-Stack or Programmers stack in Internet Explorer 9 things also work fine. I am only experiencing the issue on Stack Overflow. It started today. It was working fine on Friday.