There has been rapid progress at the Vehicle Security Center site at the south end of the WTC site that has not been discussed here. I trust relevant though, because that is crucial infrastructure for future access to the entire site and obviously interfaces with the transit hub and memorial.
See for example,
Both images from IrishinNYC at WNY. According to OP, the circular pad will be the base of a spiral access ramp that will allow vehicles to enter the WTC from street level. Personally this was news to me, I had thought the primary access would be via West Street.