I've seen the rendering for Harborside 8/9. And you can too!
Just click this link and go to page 2:
http://investors.mack-cali.com/file/...ile=1001236426
Looks taller than Urby! I'm guessing Harborside 8 is the taller one with 679 units and Harborside 9 is the two tower development, with 1,060 units.
Also interesting looking at the start dates:
25 Christopher Columbus - late 2018
Urby II - early 2019
Harborside 8 - mid 2019
Harborside 9 - beyond 2019
Urby III - beyond 2019