For Meier, playing a game is the most critical aspect of its design. Without it, he argues, the original classic would never have achieved its lofty status. It's dogma at Firaxis-everyone design. Without it, he argues, the original classic would never have achieved its lofty status. It's dogma at Firaxis-everyone plays as much as possible.
People talk, revisions are made, and they play some more.
For this reason, many of the design elements are still in flux, which means that some of what you are reading about will be tweaked, changed, or even absent. Civilizations may or may not have inherent advantages. Ditto for the special units in the game. The American F-16 or the Roman Legion may have special powers, but not if Firaxis feels it unbalances the game. Unfortunately, the same holds true for the multiplayer game.