Index: media.php
===================================================================
--- media.php	(revision 18464)
+++ media.php	(working copy)
@@ -1568,6 +1568,7 @@
 	<span><input id="cancel-upload" disabled="disabled" onclick="cancelUpload()" type="button" value="<?php esc_attr_e('Cancel Upload'); ?>" class="button" /></span>
 	</div>
 	<p class="media-upload-size"><?php printf( __( 'Maximum upload file size: %d%s' ), $upload_size_unit, $sizes[$u] ); ?></p>
+	<p class="multi-file-upload"><?php _e('<strong>Note:</strong> You can select multiple images to upload by holding down the <kbd>CTRL</kbd> key on Windows or <kbd>CMD</kbd> on a Mac.'); ?></p>
 <?php do_action('post-flash-upload-ui'); ?>
 	<p class="howto"><?php _e('After a file has been uploaded, you can add titles and descriptions.'); ?></p>
 </div>