Index: wp-admin/includes/ms.php
===================================================================
--- wp-admin/includes/ms.php	(revision 19911)
+++ wp-admin/includes/ms.php	(working copy)
@@ -658,7 +658,7 @@
 	<?php if ( in_array( get_site_option( 'registration' ), array( 'all', 'blog' ) ) ) : ?>
 		<tr>
 			<th scope="row" colspan="2" class="th-full">
-				<a href="<?php echo apply_filters( 'wp_signup_location', network_home_url( 'wp-signup.php' ) ); ?>"><?php _e( 'Create a New Site' ); ?></a>
+				<a href="<?php echo esc_url( apply_filters( 'wp_signup_location', network_home_url( 'wp-signup.php' ) ) ); ?>"><?php _e( 'Create a New Site' ); ?></a>
 			</th>
 		</tr>
 	<?php endif; ?>
Index: wp-includes/admin-bar.php
===================================================================
--- wp-includes/admin-bar.php	(revision 19911)
+++ wp-includes/admin-bar.php	(working copy)
@@ -332,6 +332,15 @@
 		) );
 	}
 
+	if ( in_array( get_site_option( 'registration' ), array( 'all', 'blog' ) ) ) {
+		$wp_admin_bar->add_menu( array(
+			'parent' => 'my-sites-super-admin',
+			'id'     => 'create-site',
+			'title'  => __( 'Create a New Site' ),
+			'href'   => esc_url( apply_filters( 'wp_signup_location', network_home_url( 'wp-signup.php' ) ) ),
+		) );
+	}
+
 	// Add site links
 	$wp_admin_bar->add_group( array(
 		'parent' => 'my-sites',