It should come as no surprise that Facebook is dwarfing the online Social Media community in the photo sharing department. As a matter of fact, the top three online photo websites when tallied (Photobucket, Picasa and Flikr) account for approximately 1/3 of Facebook's total photo inventory!
Facebook has a larger photo collection than any other site on the web. According to an extrapolation of photo upload data reported by Facebook, the site now houses about 60 billion photos compared to Photobucket’s 8 billion, Picasa’s 7 billion and Flickr’s 5 billion.
Read more at mashable.com
Photo organizing Facebook app Pixable has used data from a sample of 100,000 of its users to give some insight into the contents of Facebook’s huge photo collection.