The talk about filevault encryption that was supposedly withdrawn from the Black Hat conference was rumored not to have been submitted in the first place. Charles Edge now responds to news.com:

I submitted the talk, and later sent a second submission using the same system to then ask to be removed from consideration. As an alumni speaker, I know from experience that the entire Black Hat organization is run extremely well. Why they cannot find me in their system, I cannot speak to.

For those who can’t be at the Black Hat in person: their twitter allows you to keep updated on what’s happening!