Actually in a recent announcement on NSW infrastructure one of the projects going ahead is duplication of the rail line out of Sydney through the Central Coast exactly for freight rail.
On the Main Southern Line, significant parts of it have been leased to the freight rail companies, so if you wish to catch a scheduled passenger train, are at Mittagong station with the train at the scheduled time and a freight train wants to use the same section of track, the freight train gets the priority.
I must say that the East Hills Line (which now goes to Campbelltown) has been duplicated from Wolli Creek for freight, but I don't know how far the duplication has reached yet.
The current DNS & DC and SME at Moorebank have been "sold" to TOLL Holdings for a road/rail freight interchange. The delays are moving the Army out and completing the rail access into the site and onto the main rail corridors.

