...it would be Sparta.
Disciplined, it makes its members perfectly concise, not like those verbose chatterers of Facebook and Google+. The harsh isolation of Unfollows for those who transgress against unwritten rules. A stern framework with boundaries. Full of strange rituals, games that appear on the surface so pointless. There be wolves and other dangers and tests which all young tweeters must face.
But it's so frikkin' cool! The ladies so tough and sexy, its citizens standing up and fighting for what they believe in!
Twitter looks like a mess at first. But suddenly the enemy realises there are hundreds, maybe thousands of tribes, all standing together with one voice when they have to,
Shouting: this is Twitter!
(admitted: I learnt everything I recall about Roman history from the film 300)