We have done a number of posts in past years covering various aspects of the 9/11 terrorist attacks and the subsequent rebuilding of the World Trade Center, so today we will only be looking at some of the most recent changes.
If you go to the site of the World Trade Center in Google Earth, and turn off the 3D buildings layer, the whole square is sunk into the ground by about 20 m. We believe this was either done when it was a construction zone (and was below ground level), or, it is to stop the satellite imagery showing through when 3D imagery is turned on since the two pools do sink into the ground.
The satellite image currently in the default layer was captured on June 26th, 2016, and shows 3 World Trade Center nearing completion. According to Wikipedia, the concrete core is now at its maximum height. It can also be seen in Street View. We previously created a Street View slideshow showing the changes that have taken place over the years. We have updated it with the most recent imagery below.
We believe there are at least two major buildings still to be built at the site. World Trade Center 2 in the corner opposite the pools, and World Trade Center 5 on an adjacent block. See Wikipedia for more.