Flickr, a popular photo uploading/sharing site launched in 2004 and currently owned by Yahoo, has reached the milestone of 3 billion images. Garrett Smith, a Flickr user, has uploaded the 3 billionth photo to Flickr. Flickr reached the previous major milestone of 2 billion images last year.
Facebook, the social networking site which also has image upload facility, has 10 billion photos, and is growing at a much faster rate. This is probably because Flickr limits uploads for free users (200 photos), while Facebook has a much higher limit(1GB). Facebook is not exactly known for their photography fans, whereas Flickr is dominated by users who are truly passionate about their hobby/profession.
Flickr was originally part of a multiplayer online game, but Flickr itself proved more successful and the game was shelved. Originally founded in Canada, Flickr was acquired by Yahoo in March 2005.