The CodeIgniter YouTube API Library is designed to allow users to easily implement the YouTube API using the CodeIgniter PHP framework. This library gives users access to methods for authentication, uploading videos, rating or commenting on videos, and retrieving video feeds.
Google has released version 3.0 of the YouTube Data API which includes new functionality and features including Topics API, Universal Search, Channel Bulletin Post, Full Subscriber List Management, and more.
If you want to see in realtime what's going on Digg you can use their digg spy page. This popular Digg feature uses a dynamic Ajax UI to let you see diggs as they happen. And now it serves as a model for a growing number of mashups that use web APIs to give you a realtime window into activity on a variety of services.
No one needs an introduction to YouTube, which is by far the largest social video site. The YouTube API was first released in 2005, which seems like a long time back in the API timeline. At the recently concluded Google I/O 2012, YouTube officially announced a series of new APIs and enhancements that focused on mobile video, user engagement and Analytics.