Or better yet, the Windows Flame Malware that's using a Microsoft signed software update to hijack windows update and push Malware onto new machines using a Microsoft signed chunk of Malware.
Digital signatures aren't all they're cracked up to be. IMO Secure boot will ultimately be as successful as all the other failed systems. As soon as someone reverses the Microsoft secret key and releases it in the wild 3 years after secure boot has been in the wild you'll see the futility in the system. Doesn't matter if they have revocation lists because unless you are receiving mandatory BIOS updates you aren't going to get them.
I hope everyone can see the futility it trying to put the security into the part of the system that almost no one actually updates (BIOS). This doesn't even touch on BIOS security or code quality. All secure boot is going to do is make BIOS the target and I doubt the BIOS producers can survive the scrutiny.
All secure boot is going to do is cause there the creation of hundreds of Malware that target and exploit the BIOS. Can you imagine a world where you have to apply security updates to your BIOS on a regular basis or Windows won't load?