I was not planning to attend the conference but I still find this story very interesting. The talk I gather was pulled because the affected ATM maker(Diebold probably?) raised concerns that it would not be able to fix the flaw in time. Give me a break!
I don't know how true that is but chances are they very much knew about it and decided not to do anything. Or better yet take an ETERNITY to address the flaw. And so if that is indeed true then I believe that research as important as this should be made available to the public in order to advance the state of security.