Index: bp-core/admin/bp-core-settings.php
===================================================================
--- bp-core/admin/bp-core-settings.php	(revision 6153)
+++ bp-core/admin/bp-core-settings.php	(working copy)
@@ -49,6 +49,21 @@ function bp_admin_setting_callback_account_deletion() {
 <?php
 }
 
+/**
+ * If user has upgraded to 1.6 and chose to retain their BuddyBar, offer then a switch to change over
+ * to the WP Toolbar.
+ *
+ * @since BuddyPress (1.6)
+ */
+function bp_admin_setting_callback_force_buddybar() {
+?>
+
+	<input id="_bp_force_buddybar" name="_bp_force_buddybar" type="checkbox" value="1" <?php checked( ! bp_force_buddybar( false ) ); ?> />
+	<label for="_bp_force_buddybar"><?php _e( 'Switch to WordPress Toolbar', 'buddypress' ); ?></label>
+
+<?php
+}
+
 /** Activity *******************************************************************/
 
 /**
Index: bp-core/bp-core-admin.php
===================================================================
--- bp-core/bp-core-admin.php	(revision 6153)
+++ bp-core/bp-core-admin.php	(working copy)
@@ -286,10 +286,16 @@ class BP_Admin {
 		add_settings_field( 'hide-loggedout-adminbar',        __( 'Toolbar',        'buddypress' ), 'bp_admin_setting_callback_admin_bar',        'buddypress', 'bp_main' );
 	 	register_setting  ( 'buddypress',           'hide-loggedout-adminbar',        'intval'                                                                              );
 
-		// Allow favorites setting
+		// Allow account deletion
 		add_settings_field( 'bp-disable-account-deletion', __( 'Account Deletion', 'buddypress' ), 'bp_admin_setting_callback_account_deletion', 'buddypress', 'bp_main' );
 	 	register_setting  ( 'buddypress',           'bp-disable-account-deletion', 'intval'                                                                              );
 
+		// Only show 'switch to Toolbar' option if the user chose to retain the BuddyBar during the 1.6 upgrade
+		if ( (bool) bp_get_option( '_bp_force_buddybar', true ) ) {
+			add_settings_field( '_bp_force_buddybar', __( 'Toolbar', 'buddypress' ), 'bp_admin_setting_callback_force_buddybar', 'buddypress', 'bp_main' );
+		 	register_setting( 'buddypress', '_bp_force_buddybar', 'intval' );
+		}
+
 		/** XProfile Section **************************************************/
 
 		if ( bp_is_active( 'xprofile' ) ) {