Add custom intro text on Category archives in Thesis

add_filter( 'thesis_archive_intro', 'thesify_category_intro' );
function thesify_category_intro( $output )
{
    // set intro for featured category
    if( is_category( 'featured' ) )
        $output = '<h1>Featured Posts</h1>';
    // set intro for tutorials category
    elseif( is_category( 'tutorials' ) )
        $output = '<h1>Tutorials</h1>';
    // return the default if not on featured or tutorials
    return $output;
}