Rutkowska's got the whole story on her site. Invisible Things and Duglot's team are all good eggs, so Intel was informed about the exploit well before CanSecWest attendees got the details. The exploit itself (PDF available here) allows for privilege escalation from Ring 0 to the SMM on various newer motherboards with Intel CPUs. "Informing Intel," by the way, turns out to be the weirdest part of the story -- turns out that not only has the company known about the SMRAM-related security gap since 2005, they've mentioned it in a patent application.