That's all par for the course for Telltale, but they're doing something special with this game. Any preorder of the PC version of the Walking Dead from Telltale's site will automatically enter you into a chance to become a character in The Walking Dead game. One winner will show up in episode four as a human character who will become undead. Up to four more people will be part of the zombie horde, shambling around or possibly chewing on a victim. No purchase is necessary to enter this contest, you can also submit a postcard (details are available from the FAQ section linked from the preorder page.
The first episode of the five episode series is scheduled to be released at the end of April.