exclude-pingbacks-from-comment-count.php

<?php
//* Do NOT include the opening php tag shown above. Copy the code shown below.

// Exclude pingbacks from comment count
// change "slug" to your theme's domain
function slug_comment_count( $count ) {
	global $id;
	$comment_count = 0;
	$comments = get_approved_comments( $id );
	foreach ( $comments as $comment ) {
		if ( $comment->comment_type === '' ) {
			$comment_count++;
		}
	}
	return $comment_count;
}
add_filter( 'get_comments_number', 'slug_comment_count', 0 );