Considering the 767 will have to keep the cityflyer flag flying for at least another 4 years then this rumour might have legs!
The A330 and 787 have too big a wingspan for many of the domestic gates, hence the attractiveness of more 76's.
Qantas could then devote the 78, when they get them, to international routes.
If QF can get them for a song then I think it's a good idea.