Just thought I'd clear up a few things
All of the Merit Scholarship applicants who were short-listed received a letter in December I think, before the ATARs were released (not sure about Entry Scholarship). So it was based mostly on your academic record and personal statement (extra-curricular activities, why you are suited to Sydney etc), in the expectation that you would continue these qualities to achieve the ATAR needed for your preferred course.
Then those that actually did receive a 'provisional Scholarship offer' received a letter. It's provisional on the basis you get the ATAR for your preferred course.
Those who received a 'provisional offer' were then notified whether they needed to decline the offer if their ATAR wasn't high enough, and there was a specific time frame to do this (ie the last two weeks or so).
If there were any people who declined the scholarship because they didn't get into their course or because they accepted another offer from an alternative institution, those offers were then passed on to 'the next on the list' - so these would be the so-called 'second round scholarship offers'.
I think there is one Merit Scholarship per faculty - worth $6000 a year, plus an honours year I think. I'm not sure how many Entry Scholarships are offered per faculty.
Hope this answers a few questions!