The Pushbutton Web: Realtime Becomes Real - Anil Dash
http://dashes.com/anil/2009/07/the-pushbutton-web-realtime-becomes-real.html
Pushbutton is a name for what I believe will be an upgrade for the web, where any site or application can deliver realtime messages to a web-scale audience, using free and open technologies at low cost and without relying on any single company like Twitter or Facebook. The pieces of this platform have just come together to enable a whole set of new features and applications that would have been nearly impossible for an average web developer to build in the past.
WordPress › PuSHPress « WordPress Plugins
http://wordpress.org/extend/plugins/pushpress
This plugin adds PubSubHubbub ( PuSH ) support to your WordPress powered site. The main difference between this plugin and others is that it includes the hub features of PuSH, built right in. This means the updates will be sent directly from WordPress to your PuSH subscribers.