Index: wp-admin/includes/class-wp-posts-list-table.php
===================================================================
--- wp-admin/includes/class-wp-posts-list-table.php	(revision 21789)
+++ wp-admin/includes/class-wp-posts-list-table.php	(working copy)
@@ -670,10 +670,7 @@
 						/* translators: used between list items, there is a space after the comma */
 						echo join( __( ', ' ), $out );
 					} else {
-						if ( 'category' == $taxonomy )
-							echo __( 'Uncategorized' );
-						else
-							echo '—';
+						echo '—';
 					}
 					echo '</td>';
 					break;