Flickr for Windows Phone 7 was last updated to version 1.3 back at the beginning of March but lots of users had problems using the application because of the so called black screen issue. The issue has now reportedly been solved with Flickr for Windows Phone 7 going version 1.4  
Not much in the changelog department but the black screen bug being fixed is great news as the app can now be usable again. Additionally, there are a couple of performance and stability features and improvements in the software refresh so if you didn't receive the update notification on your Marketplace Tile, make sure to follow the source link and update..Source: Marketplace