Index: wp-includes/js/media-editor.js
===================================================================
--- wp-includes/js/media-editor.js	(revision 23348)
+++ wp-includes/js/media-editor.js	(working copy)
@@ -170,6 +170,7 @@
 				icontag:    'dt',
 				captiontag: 'dd',
 				columns:    '3',
+				link:       'post',
 				size:       'thumbnail',
 				orderby:    'menu_order ID'
 			},
Index: wp-includes/media-template.php
===================================================================
--- wp-includes/media-template.php	(revision 23348)
+++ wp-includes/media-template.php	(working copy)
@@ -347,12 +347,12 @@
 					data-user-setting="urlbutton"
 				<# } #>>
 
-				<option value="file" selected>
+				<option value="post" selected>
+					<?php esc_attr_e('Attachment Page'); ?>
+				</option>
+				<option value="file">
 					<?php esc_attr_e('Media File'); ?>
 				</option>
-				<option value="post">
-					<?php esc_attr_e('Attachment Page'); ?>
-				</option>
 			</select>
 		</label>