Hackers claim zero-day flaw in Firefox @ CNET News
It looks like they had enough information in their slide for an attacker to reproduce it. I think it is unfortunate because it puts users at risk, but that seems to be their goal.
EDIT: Mentioning the NoScript extension right about now is probably a good idea.
Edited by Mr Alpha, 01 October 2006 - 08:56 AM.