The Google Blog Search Pinging Service is a way to inform Google Blog Search of weblog updates. These updates are then published and shared with other search engines to allow them to discover the changes to your weblogs.
You can manually ping Google Blog Search and submit your blog to http://blogsearch.google.com/ping
If you are using WordPress, automatically ping it by adding http://blogsearch.google.com/ping/RPC2 in your WordPress Options.

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