We do have a thread on the forum with much of the changes documented.
They reduce the industrious trait from IIRC 200% to 150%. Forrest chops time was reduced to 4 turn, 3 if industrious.
They change the tech for sea tiles and ocean tiles to slow down the game.
The numbe of changes from large to small are numberous and many are not documented.
For CivIII player you will see corruption and the FP have been seriously impacted.