This PHP Sample Code demonstrates how to enable recognition capabilities. The application utilizes a secret ID, the images to perform recognition on, and tags.
YouTube have announced that that they are making a notable change to their YouTube API. The API, which returns results in both XML and JSON, is getting an upgrade on the JSON side, and the change is different enough that they are giving the format a new name JSON-C.
Eight APIs have been added to the ProgrammableWeb directory in categories includings Recognition, Analytics, Wi-Fi, and Home Automation. Also new are SDKs for Mixpanel mobile analytics and Untappd, a social applicaiton for beer. Here's a summary of the new additions to the directory.