I'm pretty sure services will be "normal" next week on Wed/Thurs/Fri and after New Years on Tue/Wed/Thurs/Fri.
Although I think you could expect packages coming from overseas to suffer from longer delays than normal for those 2 weeks.
I was talking to a OZ Post Contractor today and for the last 3 weeks he has been delivering 4000 packages a week...it is normally 300!!
Also he told me there have been delays in getting mail processed in Queensland.