Version: 2.3 Adds the ability to publish a post without triggering pingbacks, trackbacks, or notifying update services.
Perhaps for a particular post you don't want any external notifications sent out. If checked when the post is published, that post will not trigger the pingbacks, trackbacks, and update service notifications that might typically occur.
Yes. See the Filters section (under Other Notes) and look for the example using the 'c2c_silent_publish_default' filter. You'll have to put that code into your active theme's functions.php file.