Index: wp-admin/includes/media.php
===================================================================
--- wp-admin/includes/media.php	(revision 36173)
+++ wp-admin/includes/media.php	(working copy)
@@ -843,7 +843,7 @@
  * @param int    $post_id The post ID the media is to be associated with.
  * @param string $desc    Optional. Description of the image.
  * @param string $return  Optional. Accepts 'html' (image tag html) or 'src' (URL). Default 'html'.
- * @return string|WP_Error Populated HTML img tag on success, WP_Error object otherwise.
+ * @return string|WP_Error Populated HTML img tag (default) or image URL on success, WP_Error object otherwise.
  */
 function media_sideload_image( $file, $post_id, $desc = null, $return = 'html' ) {
 	if ( ! empty( $file ) ) {