It's an office tower that's still in development. But for now we'll just leave it at what Related has:
Now that 10 and 30 are practically full, and Related has finalized assemblage for this site, we'll begin to see and hear more as far as marketing this tower goes. But you can be the "62" will eventually shift to "80" or so.
Tishman's tower, which will be just accross the street, should also begin to come into focus. We already know what's going on with 3 Hudson.