Flickr recently added nofollow tags to most of the external links within the website. Flickr has been one of the few social sites that have allowed potential link gain from including links within the profile, comments and other areas.
Is this a surprising move? In my opinion, No. More and more social media sites are adding nofollow tags to lower the amount of spam they get hit with. You can't blame them for trying to provide clean, valuable, relevant content to their visitors / users can you? Keep in mind, you no longer can gain any link popularity from links on Flickr. However it still can generate traffic to your website. There’s a lot more benefits to using Flickr than just for links.