So the 3 on the left are Urby Harborside. The one in the middle is the existing Harborside 5 at 185 Hudson. The one on the left is Harborside 4... 1.2 million sqft of office space.
I'm already calculated the floor count for Harborside 4. The problem is it's a very large site. They could build a short stubby building at 20 floors and use the full 1.2 million sqft. Here's to hoping they only develop 1/3rd the site and leave the rest for a park.

The first pic HINTS at that - it doesn't look like it's going to be short and stubby. Looks to have a slightly larger floorplate than the Urby buildings. The curves hints at something Libeskind or Foster would design.