Though at the same time, it was the kind of overweening stuff that--like Albany's Empire State Plaza--gave bureaucratic modernism an anti-urban bad name in the 70s. (Another example: the Murrah Building, victim of the Oklahoma bombing.)
No, they have been painted.
Looking at the rendering, it appears that the support columns will not be exposed. But as can be seen, it's not entirely accurate which is not unusual.
Yes, the glass installation is the public art contribution for this project. Could have been more, but I'm sure those tree glass panels we all love cost a pretty penny.
I am excited about the art contribution across the street. Read the Burano thread for more details on that.