flush_rewrite_rules() as soon as you register the custom post type. It appears that they have not been rewritten yet, that is, most probably, why you’re getting an embarrassing message.
register_post_type( 'mysite_reviews',
array(
'labels' => array(
'name' => __( 'Reviews' ),
'singular_name' => __( 'Review' )
),
'public' => true,
'menu_position' => 5,
'rewrite' => array('slug' => 'reviews')
)
);
flush_rewrite_rules(); // <- do this only once!
Alternatively you can go to Settings -> Permalinks -> Save changes, which calls on flush_rewrite_rules() for you.
In fact http://gointrigue.com/vanilla/?post_type=mysite_reviews shows your post, which means that it’s just not being rewritten due to the lack of the proper rules, which have not yet been flushed to the database.