The game has been in closed beta testing for quite some time already, and we know relatively little about it to date. Those who have had their fair share of private testing did give off good vibes, touting the similar spirit of Civilization inside, although the gameplay might have taken a different path from what the series tend to deliver.
Since this is now in open beta, would you want to give it a go in your Facebook account, or do you prefer to stick to the old school Civilization game that is far more detailed? Granted, a game on Facebook will never come near the real deal due to the complexities involved, not to mention processing power, but with casual games having had a foothold among computer users for some time already, you can bet your bottom dollar that Civ World is going to be a hit in its own right.