They do if the developers suddenly come up with schemes to block the attack or hack the DAO. vbuterin has posted on reddit a plea for any DAO holders who were a

They do if the developers suddenly come up with schemes to block the attack or hack the DAO. vbuterin has posted on reddit a plea for any DAO holders who were about to 'split' their holdings to contact him - presumably he has a way to hack the DAO more effectively and so grab the money before the attackers grab it. But when did he know how to do this? Was it a secret that he was sitting on, or has he only learnt about it from the existing attack?