phpFlickr is a wrapper that allows developers to easily integrate the Flickr API's functions into their PHP applications. The wrapper covers functions for authentication, caching, uploading photos, and replacing photos.
Venueseen, a visual marketing and social media management solutions company, has just announced the release of the Venueseen Campaigns API allowing developers access to a powerful Instagram driven marketing tool.
Perhaps that Bing-Yahoo search deal is paying off. Even though Maps and Flickr aren't known to be part of the deal, Microsoft has connected its Bing Maps to the Flickr API in a unique way. It overlays geotagged Creative Commons photos over its current StreetSide imagery, as shown in the video embedded below.