Hi Jan,
Right now it will only show the terms associated with the taxonomy you choose (category in your case).
We could try adding it with a custom function though:
add_action( 'wpsp_after_title', 'tu_add_tags_after_title' );
function tu_add_tags_after_title() {
echo get_the_term_list( get_the_ID(), 'post_tag', '', apply_filters( 'wpsp_term_separator', ', ' ) );
}