From the Flickr Blog: We wanted to give you a heads up that Flickr will be undergoing planned maintenance this coming Thursday, July 25, from 4pm to 10pm PDT. During this time, Flickr will be unavailable on web and mobile, and the API will not be reachable. There will also be a site-wide notice an hour beforehand to make sure no one is taken by surprise. To stay on top of our updates during the outage, follow us on Twitter. Thank you in advance for your understanding. During this time you might see broken image links on the forums posted by users who have Flickr as their image host. Also obviously if you do use Flickr you won't be able to access your account. If you want updates you can follow the Twitter site linked above.