Well I looked in the default WP3 theme and this is the code you can use. In the single.php , use this code to show the category and tags wherever you like :
<?php mytheme_posted_in(); ?>
For the above to work, add this in your functions.php file :
if ( ! function_exists( 'mytheme_posted_in' ) ) :
function mytheme_posted_in() {
// Retrieves tag list of current post, separated by commas.
$tag_list = get_the_tag_list( '', ', ' );
if ( $tag_list ) {
$posted_in = __( 'This entry was posted in %1$s and tagged %2$s. Bookmark the <a href="%3$s" title="Permalink to %4$s" rel="bookmark">permalink</a>.', 'mytheme' );
} elseif ( is_object_in_taxonomy( get_post_type(), 'category' ) ) {
$posted_in = __( 'This entry was posted in %1$s. Bookmark the <a href="%3$s" title="Permalink to %4$s" rel="bookmark">permalink</a>.', 'mytheme' );
} else {
$posted_in = __( 'Bookmark the <a href="%3$s" title="Permalink to %4$s" rel="bookmark">permalink</a>.', 'mytheme' );
}
// Prints the string, replacing the placeholders.
printf(
$posted_in,
get_the_category_list( ', ' ),
$tag_list,
get_permalink(),
the_title_attribute( 'echo=0' )
);
}
endif;
For the excerpt for search and archives, use <?php the_excerpt(); ?>