XL Games is developing Civilization Online, an upcoming free-to-play MMO for the PC that will use the CryEngine 3 game engine. Contrary to the original Civilization games, this online version will not let you command an entire civilization, instead you will have control over just one character.
In Civilization Online, you will have to pick a career and as the game advances you can work your way up and get a higher position, including roles like mayor and military commander to help create order and achieve objectives - but there will also be mechanisms to oust ineffective or bad leaders. Another difference with the regular Civilization is that players will to gather resources to build structures, and that everything from clothing to transportation, weapons and other equipment will have to be made by the players.
The game will support various types of combat, including 1v1 PvP stuff but also large-scale battles and the invading of cities. When a player dies, there will be no penalty, you will not lose any items but you will resurrect in front of the town hall of your city, which means you're effectively removed from the battle due to the long travel back.
Another interesting aspect is that unlike most MMOs, the game will not go on forever. Just like the real Civilization, the game eventually comes to an end when certain victory conditions are met. When the game is over, your character's money, items and clothing will reset, but some yet-to-be-decided elements will carry over to your next game session.
The game will be published by 2K Games, but the bad news is that there are no firm plans for a global release. Initially, Civilization Online will be exclusively for South Korea, and it appears a wider release may hinge on how well the game is received in Korea.
Massively has a good article on Civilization Online, which seems to involve quite a lot of player-driven building. "Players will be able to create buildings and other structures, including full cities," the site says. Players will also be responsible for making "weapons, clothing, transportation, and other equipment." You won't necessarily have to toil as a laborer, though. Players will be able to rise up the ranks and assume more management-oriented positions, and there will be mechanisms to oust unpopular leaders.
There will also be plenty of PVP action. In addition to taking on other individual players, gamers will be able to participate in larger-scale wars with other civilizations. It looks like the game will support multiple civilizations per server, setting the stage for strategic battles between them.