Culled from one of the 20% Google projects co-creators Mihai Parparita, Brett Slatkin and Brad Fitzpatrick came up with PubSubHubbub, a way to increase efficiency across the cloud and decentralize services.

This means that instead of continuously polling or requesting for news feed updates, the feed now will automatically update or push on its own via a distributed model. There is no more waiting and updates are now close to real time.

Read more about it here: Speed in the Feed: Google Reader and PubSubHubbub