I don't think they are constructing the 'skin' upward at the tops of the two towers. There doesn't appear to be any structure being built where the glass curtainwalls end at the tops.
Unless the design changed, which would be weird with the angled bit, the crown has a few floors to go. It's not as high as the renderings yet (judging by floor count, not appearance).
ATL has long been past the point of anything proposed sub 500ft being impressive..It will take a minimum of 600ft to make a marginal mark on the skyline and 700ft+ to astound...