Index: wp-content/themes/twentythirteen/functions.php
===================================================================
--- wp-content/themes/twentythirteen/functions.php	(revision 23465)
+++ wp-content/themes/twentythirteen/functions.php	(working copy)
@@ -528,6 +528,23 @@
 add_action( 'template_redirect', 'twentythirteen_content_width' );
 
 /**
+ * Adjust embed defaults for video post formats.
+ *
+ * @since Twenty Thirteen 1.0
+ */
+function twentythirteen_embed_defaults( $defaults ) {
+	$post = get_post();
+
+	if ( ! empty( $post ) && has_post_format( 'video' ) ) {
+		$defaults['width'] = 724;
+		$defautls['height'] = 1000;
+	}
+
+	return $defaults;
+}
+add_filter( 'embed_defaults', 'twentythirteen_embed_defaults' );
+
+/**
  * Adds entry date to aside posts after the content.
  *
  *
Index: wp-content/themes/twentythirteen/style.css
===================================================================
--- wp-content/themes/twentythirteen/style.css	(revision 23465)
+++ wp-content/themes/twentythirteen/style.css	(working copy)
@@ -1735,6 +1735,14 @@
 	background-color: #dd5625;
 }
 
+.format-video .entry-content embed,
+.format-video .entry-content iframe,
+.format-video .entry-content object,
+.format-video .entry-content video {
+	margin: 0 -60px;
+	max-width: 724px;
+}
+
 .format-video .entry-content a,
 .single-format-video .entry-content a {
 	color: #fbfaf3;