I’ve just upgraded to 1.0. I have bbpress integrated with custom website, not WP.
1. pluggable.php is changed to functions.bb-pluggable.php.
2. some functions are renamed from wp_ to bb_, others aren’t.
3. bb_auth() is used sometimes. And sometimes is not.
4. localization directory is changed.
As a result, my forum needed second full integration. I had to add bb_auth() at the bottom of my bb-custom-pluggable.php to maintain user login, with $wp_auth_object->set_current_user($id) inside.