@duncanmonza – I doubt it. The 2013 V8 Supercars calendar hasn’t been released yet, but I don’t think either series would want to be seen as supporting the other. And the circuit has taken criticism for the use of “Personal Seat Licences”, which is modelled on an NFL system when you can buy a seat for a year; it’s a problem, because right now, the circuit only has three events: the United States Grand Prix, V8 Supercars, and now ALMS (the state of the MotoGP round is unclear). It’s currently very difficult to justify buying an expensive PSL, and it will be even moreso if they merge V8 Supercars and ALMS into one weekend.
So it’s in everyone’s interests to keep the races separate.