Index: wp-admin/includes/class-wp-posts-list-table.php
===================================================================
--- wp-admin/includes/class-wp-posts-list-table.php	(revision 17420)
+++ wp-admin/includes/class-wp-posts-list-table.php	(working copy)
@@ -476,7 +476,7 @@
 		$title = _draft_or_post_title();
 		$post_type_object = get_post_type_object( $post->post_type );
 		$can_edit_post = current_user_can( $post_type_object->cap->edit_post, $post->ID );
-		$post_format = get_post_format( $post->ID );
+		$post_format = post_type_supports( $post->post_type, 'post-formats' ) && get_post_format( $post->ID );
 		$post_format_class = ( $post_format && !is_wp_error($post_format) ) ? 'format-' . sanitize_html_class( $post_format ) : 'format-default';
 	?>
 		<tr id='post-<?php echo $post->ID; ?>' class='<?php echo trim( $rowclass . ' author-' . $post_owner . ' status-' . $post->post_status . ' ' . $post_format_class); ?> iedit' valign="top">
Index: wp-admin/includes/template.php
===================================================================
--- wp-admin/includes/template.php	(revision 17420)
+++ wp-admin/includes/template.php	(working copy)
@@ -1647,7 +1647,7 @@
 		}
 	}
 
-	if ( get_post_format( $post->ID ) )
+	if ( post_type_supports( $post->post_type, 'post-formats' ) && get_post_format( $post->ID ) )
 		echo ' - <span class="post-state-format">' . get_post_format_string( get_post_format( $post->ID ) ) . '</span>';
 }
 
Index: wp-includes/post.php
===================================================================
--- wp-includes/post.php	(revision 17420)
+++ wp-includes/post.php	(working copy)
@@ -487,6 +487,9 @@
 function get_post_format( $post = null ) {
 	$post = get_post($post);
 
+	if ( ! post_type_supports( $post->post_type, 'post-formats' ) )
+		return false;
+
 	$_format = get_the_terms( $post->ID, 'post_format' );
 
 	if ( empty( $_format ) )