Last August, when a 5.8-magnitude earthquake shook Virginia, people in offices up the East Coast were reading about the quake before they felt their desks not-so-mysteriously begin to wobble. How? Chalk it up to another feat of Twitter (by this time it had already helped topple unruly regimes in the Middle East). During the earthquake, users tweeted at a rate of 5,500 tweets per second, with 40,000 tweets hitting Twitter timelines and TweetDecks in just one minute.

