even when a new comment is flagged "awaiting moderation", it is still displayed. This is true on 2 different installations using 2 different themes. The only comment plugin I have is Akismet.
In wp-includes/comment-template.php (dated 2009-12-14) I see
if ($comment->comment_approved == '0') : ?>
<?php _e('Your comment is awaiting moderation.') ?>
then, endif followed by displaying the comment etc. ... regardless of whether it is to wait for moderation.
what happened to <&php else: ?> [display the comment etc.] ... endif.
(you get the idea)
Is the logic somewhere else? ... where we can find the conflict?