Just as something to put out there, all of the proposals were in the 500-600m range. I can back this with some findings, mostly new proposals for this project, which is being called "Z3" or "Z3 Tower".
On Adrian Smith's website, I found this under Robert Forest's project experience:
Architectural design for 550 meter supertall tower in Pudong district to complete original Pudong-Shanghai Masterplan, 2006, Shanghai, China"
I also found a new rendering from a different firm, here:
and a video of a proposal sent in by some students.
Thats just some of what I found, many more proposals, but pointless to post them as it seems that the city wants a green building, with most not qualifying.