Is it possible to change the "add new comment" text on certain content types? Is it possible to change the "add new comment" text on certain content types?  Also is it possible to only allow certain roles to post comments on this content type?
Check the roles/permission grid to restrict certain roles posting comments.

hook_node_view_alter(&amp;$build) would help to replace the label with your custom one.

e.g.

 function MODULE_node_view_alter(&amp;$build){
    if ( in_array($build['#node']-&gt;type, array('page')) )
    $build['links']['comment']['#links']['comment-add']['title'] = l('New Label', 'comment/reply/'. $build['#node']-&gt;nid);


There can be another easy way using String Overrides but it will not let you  do on specific content types.