How to make "Announce on LinkedIn" on by default?
The issue here is the LinkedIn post functionality is tied to the node form; the form is altered to add the form component &amp; submission hook. However, Feeds isn't using this form so it will never get a chance to process the submission handler.

If you look at the submission handler you can pull out the relevant function, linkedin_put_profile_field(),  to make this happen. Combine this with hook_feeds_after_import(), and you can come up with an implementation that will trigger a LinkedIn post upon a feed import:

function MYMODULE_feeds_after_import(FeedsSource $source) {
  if(function_exists('linkedin_put_profile_field') &amp;&amp; isset($source-&gt;feed_nid) &amp;&amp; $node = node_load($source-&gt;feed_nid) {
    $status = variable_get('linkedin_default_format_'. $node-&gt;type, '');
    linkedin_put_profile_field($node-&gt;uid, 'current-status', $status);
  }
}


Note: there will probably need to be more checks &amp; altercations here based on your needs (e.g. setting the right UID to post as, throttling posting so your feed importing doesn't get marked as spam on LinkedIn).