I won’t question your adeptness at a favorite childhood game, but my bot Herbert will. Myself and a few other guys developed Herbert for our final project in AI class, and he is frustratingly unbeatable. After a game or two against him, you might consider an early retirement from the Connect 4 world. [Update 3/3/2012 I have uploaded Herbert for you to download and play against. See details at bottom of this post for more]
Andy G's Blog 