From CC.au license
-attribute the original author in any work, derivative work or collection that you distribute. The attribution may be provided in any reasonable manner, but as far as is reasonable to the medium...
thought:
attribution in the credits of a film might have been created to make sure the artists could be compensated for their work through a guild, possibly? what percentage of an audience reads the credits of a film? What about the time and placement of the creativity within the film? Most films have a q-sheet (that is separate to the film) that lets the rights authority know what was played when and by who- so royalties can be distributed. Would this q-sheet need to be part of the attribution as the most minimum form of reasonable attribution?
my point is that a lot of mediums have no form of reasonable attribution. Maybe a link from the license could list different ways to attribute, a set of standards for each medium to make sure creators are attributed fairly.