The stock exchange building was mentioned before a few months ago, when Melbourne was stated as a target. The Rialto across the road might also be a target.
If NY and London are used as examples (sounds morbid, but we are analysing things here, since both of us live in Melb), there might be several targets.
The Melb. central building with the underground station is a likely target. Parliament House with the station across the road, might be another.
