How many tweets does an earthquake make?

If a tree falls in the woods and no one is around to send a tweet about it, did it really fall? This is the question I've been trying to wrap my head around today, after reading Steve Gillmor's latest missive from the realtime future (where they speak a somewhat different version of English than we do at present). Gillmor reports on a seismic event that happened near his home earlier today: This morning I felt a jolt and reached for my iPhone to check in with my wife on the highway. She immediately asked whether it was on Twitter... http://ping.fm/Cj4iP