I've been discerning heights for my Boston/Minecraft project from Google Earth. Just note the elevation of the building when you put your cursor over it and compare it to the elevation of the ground below. Easy and accurate to within a foot or two.
Big issue is whether or not some tiny spire might be throwing the height out of whack. I wonder that about the Fed for sure. (with all those sticks on top) 33 Arch has an extra, barely visible spire on the middle fin that surely contributes to that 477' figure.
Also, it seems like mech tops generally count, which makes me wonder if the Pregnant Building is really taller (Exchange Place too). A good example of this is the IDS Tower in Minneapolis. For years and years it was billed as 772', but suddenly they realized the small box at the top counted and it jumped the Hancock to 792'.
If you find any buildings that should be taller (Exchange Place, Preggers, 1 Financial) we should definitely report those numbers to the appropriate places. If you find any that appear shorter (Fed, for instance) it's probably better to do more research than to automatically downgrade them statistically.
Yes I am a homer and that is a homer approach but what can you do?
Regarding this one, I'm curious as to people's guesses for the following dates.
Any steel/concrete out of the ground: My guess, December 7. (EDIT, revising this to November 30, thanks for the pics Beeline!)
Entire hole filled to at least ground level: My guess, December 29.
Top out: My guess, October 4.