Is it built from bare Corten steel and left to rust?
If so it might rust to a more uniform colour, but no one will ever see it like that. It will be a magnet for graffiti and posters.
Sadly this prediction has alrady come true. The street side of the building is already tatty, 1 day after opening. http://melbourneontransit.blogspot.com/2011/01/bringing-stations-to-life-cafe-3162.html
As Craig mentioned, integration with the surrounding urban environment and the station is limited. Architects are too often still designing buildings that back onto the railway.
What would I have done instead?
Instead of building something I'd have got out the wrecking ball, demolishing most billboards, walls and buildings on Platform 4.
There'd still be shelter, toilet and waiting area but there would be much better visibilty between the platform and the shops etc on the other side of Sir John Monash Drive.
This improves perception of safety and makes the station more a part of the city rather than a seperate structure.
I'd also favour traffic calming on more of Sir John Monash Dr. And a second platform 4 exit on the down end of Platform 4, near where Cafe 3162 currently is. If aligned with a new pedestrian crossing this would cut access time to Monash Uni and the 900 SmartBus from 2-3 min to maybe 30 sec.