This is sort of known, but I thought still worth talking among you fellow (few?) Dead Island fans.
In this screenshot of the game's menu we see three bits of unlockable content. The Ripper Mod is the weapon blueprint you get with a pre-order of the game. The Bloodbath Arena is a $US10 downloadable pack already announced by Techland. So what is Ryder White's Campaign? It sounds like, knowing the story, it could be a vastly different way to play through the entire game, or at least a complete Act of the game.
What do you think? Personally, I'd love to play through White's pre-game story. I'd REALLY love to play his campaign through till the end of the entire game. If you know what I mean. WINKIE!