Real-Time Feeds on Your Website via Google Feed API 2.0
RSS/Atom feeds typically use PubSubHubbub (PUSH) to actively push any fresh content to feed subscribers within mere seconds of being published. The Google Feed API 2.0 takes the PUSH-enabled feeds and publishes them to the sites with the embedded feature immediately, whereas the Feed API 1.0 could often take hours to show the update.
The information about Google Feed API 2.0 was released via an unlisted YouTube video. YouTube's new "unlisted" privacy feature enables users to publish videos that are only accessible via direct links. Once the video was discovered, Google confirmed the news about Feed API 2.0 and announced that it would be launching on the first day of Google I/O 2010.