Correct me if I am wrong but the “theme editor” in WordPress is simply a remote file editor for templates. Doesn’t do anything special other than let you edit a file directly on your server without having to use FTP (or shell).
While it seems handy, if I am not mistaken it also requires you to chmod 777 your theme folder which is very dangerous on a shared server.
I suppose bbPress will get the feature eventually because it’s so very simple. I would guess it could be ported from the WordPress code in probably an hour.