rflickr is a Ruby implementation of the Flickr API. It includes a faithful reproduction of the published API as well as method encapsulation to provide more useful object mappings. rflickr features result caching to improve performance.
Flickr has added more real-time goodness to their photo API. Using a publish / subscribe (PubSub) system, developers can now receive real-time updates across millions of photos across Flickr friends, Flickr Commons, and by tags and geo-location using the Flickr Real-Time API.
For those who like to dabble with a bit of photo editing but aren't really inclined to pursue more advanced and sophisticated tools like Photoshop, an online photo ending tool like Ribbet may be just what they're looking for. This app may not give you the most groundbreaking features when it comes to cutting edge image editing, but it certainly has appealing functions that are easy to use and easy to access online, allowing users to get really creative with their photos. What's also cool is that developers can integrate this photo editor into their websites, using the Ribbet API.
Finally, you have definitive proof that your significant other is only 52% happy. Face detection and recognition service Face.com has been busy since it launched its free API a year ago. The company has been adding servers to handle the load of the over 20,000 developers who signed up. It's also been adding features, the most recent the ability to detect the mood of a face, along with a confidence rating.