WordPress: edit user fields

gistfile1.php

// Add customer user fields in wp admin
function modify_contactmethods( $contactmethods ) {
	// Remove unwanted fields //
	unset($contactmethods['aim']);
	unset($contactmethods['yim']);
	unset($contactmethods['jabber']);
	// Add new fields //
	$contactmethods['twitter_handle'] = 'Twitter Handle (@)';
	$contactmethods['linkedin_url'] = 'LinkedIn Profile (URL)';
	return $contactmethods;
}

add_filter('user_contactmethods','modify_contactmethods');