A reader writes:

You know what struck me about your infographic here? Almost all of those Facebook locations are hotspots for backpacking and travel abroad activity. Whenever I backpack abroad the one thing I can be sure of is that everyone I meet is using Facebook to log the people they meet in their travels. I can't help but imagine the proliferation of Facebook had a little something to do with seeds planted by travelers like myself. You pop into a hostel's computer room and everyone is on facebook, sending invites to those they've met or messaging friends back home. The social network is at its most useful when you're bouncing around the globe.

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