// Add post types of "Talk" and "Event"
function nc_custom_post_types() {
    register_post_type( 'talk',
        array(
            'labels' => array(
                'name' => __( 'Talks' ),
                'singular_name' => __( 'Talk' )
            ),
        'public' => true,
        'has_archive' => true,
        'taxonomies' => array('talktype', 'category'),
        )
    );
    register_post_type( 'event',
        array(
            'labels' => array(
                'name' => __( 'Events' ),
                'singular_name' => __( 'Event' )
            ),
        'public' => true,
        'has_archive' => true,
        )
    );
}
add_action( 'init', 'nc_custom_post_types' );