Much has been made of the new hex maps and how they will change gameplay. Maps certainly look better as hexes than squares, but the real change in the game is the military model. Civilian units can stack with others, but army units cannot so you get one unit per hex. The objective was to move combat away from just city sieges and into the battlefields. A single unit per hex means that a smaller army can use terrain and experience to its advantage (guarding a mountain pass, for example) and allows Firaxis to introduce ideas like flanking bonuses (seen in the combat calculations but not commented on) for attacking enemies you've surrounded. Ranged units can use defensive fire to protect the armies they are supporting as well as target enemies on attack, and battles are no longer kill or be killed. Both units might come away from a battle weakened but not destroyed. Armies will be smaller than those in earlier Civs, but their composition will be much more important.

Cities will have hitpoints instead of stacks of defenders. Larger cities will need to be pounded into submission. Transoceanic invasions will involve less micromanagement (any unit can become its own transport – and a stackable civilian unit when it does so) but more naval warfare preparation (since these transports have no defensive power whatsoever). In sum, the military system will be something more than a production race.

Firaxis is adamant that diplomacy not be given short shrift. Only a few diplomatic changes were on display, but the addition of city states as catalysts for conflict will make the diplomatic game more dynamic. These small nations will never grow past their single city, but their friendship can earn general bonuses for your entire civilization. Protecting or preying on them opens up new possibilities for small wars growing into bigger ones.

Since religion ended up being just another diplomatic metric in Civilization IV, it's been taken out. Firaxis PR associate Pete Murray assured the audience that the idea of religion being represented has not been entirely cast aside, but he would not elaborate on how this crucial component of human history would take form in the new vision.

Even without hands on experience, it's quite clear that this Civilization will mean as many adjustments for players as its predecessor. Lead designer Jon Shafer is putting his own imprint on the series, emphasizing some things (larger differences in play variety) and de-emphasizing others (the production arms race). The cleaner and brighter look is almost an omen of clean skies ahead for the franchise, a new world full of possibilities. But new worlds have dangers, too, and until we see how the game plays through the millennia it will be difficult to gauge just how everything fits together.