RMS (formerly the RTA) is introducing a new system of road numbering and new names for some important routes. The changes will commence in early 2013 and should be fully implemented by the end of that year.
The changes are simple in that they apply a letter and number code to Motorways (M), roads of national significance (A) and roads of state significance (B). The numbers identify the different motorways or roads within each category.
The changes will make navigation on major routes much simpler. For example, if want to drive to Broken Hill from Sydney, you will simply follow the A32 the whole way. If you want to drive from Sydney to Walgett you join the B55 and follow it through to Walgett.
The changes are consistent with systems in most other states so that the same code will apply as roads cross into those states.
Name changes will apply to some major roads, however the changes are not significant and should not have a major impact.
More information is available on the RMS website.