Do the Right Ping
Wikipedia says that pinging is:
an XML-RPC-based push mechanism by which a weblog notifies a server that its content has been updated. An XML-RPC signal is sent to one or more “ping servers,” which can then generate a list of blogs that have new material.
If you log in to your WP admin panel and click Settings > Writing on the left hand side menu, at the bottom of the resulting page you will see a field called “Update Services.” By default, all WP sites use http://rpc.pingomatic.com/, which you should see listed in the box. However, there are many pinging websites to choose from, and some may suit your needs better than others. A simple Google search yields dozens, if not hundreds of options.
Don’t get carried away
While you undoubtedly want as many content aggregators to know about your site so you can bring lots of visitors, you’ll also need to be careful not to get carried away: Ping one source more than three times and you could get marked as a ping spammer. Hence, it’s often best to let one pinging site do its work rather than try to incorporate several at once. As it happens, Pingomatic, the WP default, is an excellent service.
Still curious about what’s out there? A programmer and designer named Aaron Boundy recently did some fastidious research and provided a definitive list of ping servers for 2010/2011. Read his full list here.
Among the best out there:
Note: If you’re on a WordPress Multisite network, pinging services are deactivated by default. To turn them back on, you’ll need this plugin: