It’s indeed a custom font created by a designer called
Joe Kral.
(‘Klavika Bold’ is accepted as the closest font you can get):
http://www.myfonts.com/fonts/processtype/klavika/bold/
Edited on Jan 29, 2013 at 01:41 by rocamaco
It is a custom font, indeed. Klavika is close, but the font Facebook Letter Faces is based on the logo, so I think that is the best one.
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