There's only so many place you can tweet from, and Twitter's been diligently indexing them all. These new visualizations from the Twitter team organised for this sort of thing show the history of all geo-tagged tweets since 2009 (when the feature was born) by location. We're talking billions of them.
We've seen this sort of thing before, whether it's Twitter and Flickr usage across the country illustrated by bursts of light, or Foursquare check-ins displayed the same way. And hopefully we'll never stop seeing them, because they're always awesome.
Looks like folks out west don't find much use in geo-tagging their tweets as "in the middle of a field in the middle of nowhere" (I KID!) and if you're looking for a new place to tweet from on the isle of Manhattan, good luck; you'll need it. [Twitter Blog via The Verge]