Some of the greatest games I have ever played were under 10 hours. I am they type of gamer that doesn't care about extra's nor multiplayer.
Gears of war, metal gear solid and metal gear solid 2 and shadows of the colossus are the few games off of the top of my head in which I finished very quickley but enjoyed them so much I honestly couldn't complain. All of them had great replay value because they were such good games.
Honestly, anyone who has been gaming as long as I have, really wouldn't be complaining about multiplayer or extra's in a video game. Now most of the extra's are just a time sink and multiplayer is viewed as a welcome addition instead of a requirement. Give me a polished game and ill be satisfied, look at bioshock. Single player and if you wanted to you can blow through the game.
Games make me happy! 
PSN ID: Staticneuron
Gamertag: Staticneuron
Wii Code: Static Wii - 3055 0871 5802 1723
