DAB+ has been allocated TV channels 9 and 9A. Which gives 8 DAB+ transmission channels which requires over 300 km between high power transmitters. So to put DAB+ into areas surrounding all mainland capital cities except Perth all 8 channels will be required, assuming the ABC is single frequency networked.
DAB+ now has 25 % of the audience in these cities.
All areas of Australia has been allocated 6 TV channels per transmitter site for on new network.
SBS HD is presently 1140 x 1080 and not 1920 x 1080 used by the commercials, the conversion to MPEG-4 halves the data rate, which SBS has now increased to match all other broadcasters. This is why channels 70, 80, 90, 13 are all MPEG-4. They have retained their 3 secondary channels and an SD version of their primary program.
If you look at the ratings for all secondary channels especially those of SBS they have tiny number of viewers. What is required is some leadership from the Department of Communications/ACMA to get all broadcasters to convert all programs to MPEG-4 and leave an SD MPEG-2 primary channel for each broadcaster on air for a year.
After all, we had analog TV which could not receive digital signals switched off. It is now nearly 7 years since MPEG-4 TVs appeared in the Australian market.
What is really required is a survey to determine what proportion of TVs cannot receive MPEG-4. No one really knows. How long do we wait for people to buy new much cheaper TVs>