Straight lines don't exist in the human form and are extremely rare in nature, so the human touch in the logo is that all the lines and forms have at least a slight curve.
Marissa MayerTheres no such thing as Flickr Pro because today, with cameras as pervasive as they are, theres no such thing, really, as professional photographers when theres everything thats professional photographers. Certainly theres varying levels of skills but we didnt want to have a Flickr Pro anymore. We wanted everyone to have professional quality photo space and sharing.
Marissa Mayer