jQuery Plugin Lab

What's wrong with this plugin?

by vijayram_a

HTML

<a href="http://www.google.com" rel="external">Google</a>
<a href="http://www.yahoo.com" rel="external">Yahoo</a>
<a href="http://www.bing.com" rel="external">Bing</a>
<a href="#" class="local">Local</a>

JavaScript

/**
 * Externalize Plugin
 * 
 * configures links that relate to external sites open in a new tab,
 * colors them red and appends an arrow to indicate that it is external
 */
$.fn.externalize = function() {
    
    if(this.attr('rel') == 'external') {
     
        this
            .attr('target', '_blank')
            .append('\u2B00');
        
    }
    
};
 
$( "a" )
    .externalize()
    .filter('.local')
        .css('font-weight', 'bold');