A section of the credits called "Forum Crew" lists a specific list of Telltale message board users.
The spoiler warning at the beginning is different every time you start up the disc.
At the end of the end credits it says, "When online, visit MaxForPresident.org" (as of 2017, that website is no longer online). This is likely a reference to the famous, "When in Hollywood, Visit Universal Studios" bumper that appeared at the end of many Universal Pictures films, most notably National Lampoon's Animal House (1978).