<?php
// Query Tag Filter
$wpse47974_filter = '';
if ( isset( $wp_query->query_vars['wpse47974_filter'] ) && in_array( $wpse47974_valid_filters, $wp_query->query_vars['wpse47974_filter'] ) ) {
    $wpse47974_filter = $wp_query->query_vars['wpse47974_filter'];
}
?>
<?php
// Define an empty array to hold our filter parameters.
// This needs to be an array, in order not to generate
// errors later in the array_merge(), if no filter parameters
// are being applied to the default query
$wpse47974_filter_args = array();

// If our query var is set, apply the filter parameter
if ( '' != $wpse47974_filter  ) {
    $wpse47974_filter_args['r_sortby=highest_rated'] => 'top-rated';
};
?>
<?php
// Globalize $wp_query
global $wp_query;
// Merge the default query with our filter parameters
$wpse47974_query_posts_args = array_merge( $wp_query->query, $wpse47974_filter_args );
// Modify the default query
query_posts( $wpse47974_query_posts_args . "cat=-1&paged=".get_query_var('paged'));
while ( have_posts() ) : the_post(); ?>