From the talks at
Digital Media Analysis, Search and Management workshop at Calit2, 2/27-2/28, 2012
talk 1:
Facebook - 3 billion photo uploads a month
Flickr - 5 billion photos in total
Flickr - %85 of photos have no tags or descriptions
Picassa - only %5 of photos contain tags
%60 of consumer photos contain faces
talk 2:
500 billion consumer photos taken per year
36 billion Facebook photos now
40K photos uploaded per minute