If you use WordPress and want to enable PubSubHubbub on your own blog, you can do so by installing the PubSubHubbub Wodpress plugin. By default, all blogs hosted on WordPress.com already use this protocol to send out real-time updates, as do all blogs on Blogger and Posterous.
If you’re using Feedburner to manage your RSS feeds, you can also turn on Google’s PingShot service and sent out PubSubHubbub announcements in real time
via Has Google Reader Gone Real Time?.
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