How the secret list will be abused:

Electronic Frontiers Australia (EFA) found themselves on a blocked list run by SurfWatch in 2000. The EFA does not have and has never had explicit content... however, they have always objected to internet filtering.

Link:

Rhetoric from the current government suggests that everything is different now and that lists will be carefully (but secretly) maintained. I suggest that every site criticising the idea will be on the list. History doesn't repeat but it often rhymes.