comment-loggedin-tweak.php

<?php 

add_filter('comment_form_defaults', 'endo_comment_changes');

function endo_comment_changes( $defaults ) {
	
	$current_user = wp_get_current_user();

	$defaults['logged_in_as'] = '<p class="logged-in-as">' . sprintf( __( '<small>You are currently logged in as <a href="%1$s">%2$s</a> ... Is this not you? <a href="%3$s" title="Log out of this account">Log out by clicking here.</a></small>' ), admin_url( 'profile.php' ), $current_user->user_login, wp_logout_url( apply_filters( 'the_permalink', get_permalink( ) ) ) ) . '</p>';

	return $defaults;

}